Auto injector with temperature control

ABSTRACT

Disclosed is an auto injector and a method for administering a medicament. The auto injector comprising: a housing; a cartridge receiver; a drive module coupled to move a plunger rod configured to move a first stopper; a temperature sensor configured to provide a temperature signal indicative of the temperature of the medicament in the cartridge; a processing unit configured to: receive the temperature signal; control the drive module to move the plunger rod from a first plunger rod position to a mix plunger rod position wherein the movement from the first plunger rod position to the mix plunger rod position is based on the temperature signal.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a U.S. National Phase Application of PCTInternational Application Number PCT/EP2016/082857, filed on Dec. 29,2016, designating the United States of America and published in theEnglish language, which is an International Application of and claimsthe benefit of priority to European Patent Application No. 15203168.8,filed on Dec. 30, 2015, and European Patent Application No. 16190461.0,filed on Sep. 23, 2016. The disclosures of the above-referencedapplications are hereby expressly incorporated by reference in theirentireties.

The present disclosure relates to an auto injector, such as anelectronic auto injector, a cartridge for an auto injector, a systemcomprising an auto injector and a cartridge, and a method for operatingan auto injector.

BACKGROUND

Hypodermic syringes are widely used to deliver fluids to the body. It isknown to have hypodermic syringes applicable for manual operation.However, auto injectors, such as electronic auto injectors, have beendeveloped and are widely used to aid the administering of fluid ormedicaments to the body.

To avoid relying on users correctly performing certain tasks, it is ofincreasing interest that the auto injector automatically carries out asmuch as possible of the injection process. Especially, whenadministering of the medicament requires several steps, such as ifmedicament needs to be mixed prior to injection, it may be beneficial toautomate the process of preparing and administering the fluid, such as amedicament.

Furthermore, it may be advantageous to incorporate sensors into suchdevice, to allow for a precise control in varying circumstances.

SUMMARY

There is a need for an auto injector, such as an electronic autoinjector, with an improved automation of preparing and administering themedicament. The present disclosure provides an auto injector, acartridge, a system, and a method improving the preparation andadministering of medicament with an auto injector.

Accordingly, an auto injector for preparing and/or administering amedicament, such as a medicament from a cartridge is disclosed.

The auto injector comprises: a housing; a cartridge receiver; a drivemodule; a temperature sensor; and a processing unit.

The cartridge receiver is configured to receive a cartridge, such as acartridge comprising a first stopper and a cartridge compartmentcontaining the medicament. The cartridge compartment has a firstcartridge subcompartment containing a first medicament component of themedicament and a second cartridge subcompartment containing a secondmedicament component of the medicament.

The drive module is coupled to move a plunger rod between a retractedplunger rod position and an extended plunger rod position. The plungerrod is configured to move the first stopper.

The temperature sensor is configured to provide a temperature signalindicative of the temperature of the medicament in the cartridge, e.g.when the cartridge is received in the cartridge receiver.

The processing unit is coupled to the temperature sensor and the drivemodule. The processing unit is configured to: receive the temperaturesignal; control the drive module to move the plunger rod from a firstplunger rod position to a mix plunger rod position; control the drivemodule to move the plunger rod from the mix plunger rod position to asecond plunger rod position after a reconstitution time has elapsedsince completion of movement of the plunger rod to the mix plunger rodposition.

The mix plunger rod position is selected to position the first stopperin a position wherein the first medicament component is mixed with thesecond medicament component.

The processing unit is further configured to control the drive module tomove the plunger rod from the first plunger rod position to the mixplunger rod position with a mix plunger rod speed. The mix plunger rodspeed may be constant speed or a varying speed.

The movement from the first plunger rod position to the mix plunger rodposition is based on the temperature signal. For example, the processingunit may be configured to control the drive module to move the plungerrod from the first plunger rod position to the mix plunger rod positionbased on the temperature signal.

Also disclosed is a cartridge for an auto injector, such as thedisclosed auto injector. The cartridge comprises a first stopper and acartridge compartment containing the medicament. The cartridgecompartment has a first cartridge subcompartment containing a firstmedicament component of the medicament and a second cartridgesubcompartment containing a second medicament component of themedicament. The cartridge may have a first cartridge end and a secondcartridge end and have a cartridge outlet at the first cartridge end.The cartridge is configured to be received by a cartridge receiver of anauto injector, such as a cartridge receiver of the disclosed autoinjector, e.g. by insertion of the second end of the cartridge through acartridge receiver opening of the auto injector.

Also disclosed is a system comprising an auto injector, such as thedisclosed auto injector, and a cartridge, such as the disclosedcartridge.

Also disclosed is a method for operating an auto injector, such as thedisclosed auto injector, e.g. an auto injector comprising a cartridgereceiver configured to receive a cartridge, such as the disclosedcartridge, e.g. a cartridge comprising a first stopper and a cartridgecompartment containing the medicament, the cartridge compartment havinga first cartridge subcompartment containing a first medicament componentof the medicament and a second cartridge subcompartment containing asecond medicament component of the medicament. The auto injector mayfurther comprise a plunger rod configured to move the first stopper, anda temperature sensor.

The method comprises: receiving the temperature signal from thetemperature sensor indicative of the temperature of the medicament;moving the plunger rod from a first plunger rod position to a mixplunger rod position with a mix plunger rod speed, wherein the mixplunger rod position is selected to position the first stopper in aposition wherein the first medicament component is mixed with the secondmedicament component, and wherein the movement from the first plungerrod position to the mix plunger rod position is based on the temperaturesignal; moving the plunger rod from the mix plunger rod position to asecond plunger rod position after a reconstitution time has elapsedsince completion of movement of the plunger rod to the mix plunger rodposition.

The first plunger rod position may be a pre-mix plunger rod position.The pre-mix plunger rod position may be selected to position the firststopper in a position wherein fluid communication between the firstcartridge subcompartment and the second cartridge subcompartment is notyet established. Alternatively, the first plunger rod position may be aretracted plunger rod position, e.g. an initial plunger rod position.

The second plunger rod position may be a prime plunger rod position. Theprime plunger rod position may be selected to position the first stopperin a position wherein air in the cartridge compartment is reduced to anamount appropriate for injection. Alternatively, the second plunger rodposition may be an injection plunger rod position. The second plungerrod position may be the extended plunger rod position.

The method may further comprise receiving a trigger event; and movingthe plunger rod to an injection plunger rod position following receptionof the trigger event, e.g. after completion of movement of the plungerrod to the second plunger rod position.

The trigger event may, for example, be an effect of a push of a button,an effect of an elapsed timeout, and/or an effect of a predetermineduser behaviour. The trigger event may be indicative of the auto injectorbeing pressed against the injection site.

It is an advantage of the present disclosure that the steps involved inpreparing and/or administering a medicament are increasingly automated.It is further an advantage that such increased automation provides forincreased safety in preparing and/or administering the medicament.

It is a further advantage of the present disclosure that an autoinjector may be provided which is easier to use, and reduce the risk oferroneous administering of a medicament.

It is a further advantage of the present disclosure that an autoinjector may be operated according to the temperature, such as thetemperature of the medicament, e.g. to increase precision in theoperation of the auto injector.

Thus, it is a further advantage of the present disclosure, that patientsafety is increased.

It is envisaged that any embodiments or elements as described inconnection with any one aspect may be used with any other aspects orembodiments, mutatis mutandis.

The cartridge may have a cartridge outlet at the first cartridge end.The cartridge may comprise a cartridge back face, e.g. at the secondcartridge end, such as opposite the cartridge outlet. The cartridge backface may comprise a cartridge back end opening.

The cartridge back end opening may provide access for a plunger rod,such as the plunger rod of the auto injector, to the first stopper.

The cartridge compartment may contain the medicament. The cartridgeoutlet may be configured for fluid communication with the compartment,e.g. at the first cartridge end. The cartridge may be configured toexpel medicament through the cartridge outlet. The cartridge outlet maybe configured to be coupled with a needle, such as a hypodermic needle,to provide the medicament to be expelled through the needle.

The cartridge comprises a first stopper movable inside the cartridgecompartment. The cartridge may comprise a second stopper movable insidethe cartridge compartment. The second stopper may be between the firststopper and the cartridge outlet. The cartridge may comprise a thirdstopper movable inside the cartridge compartment. The third stopper maybe between the second stopper and the cartridge outlet. The firststopper, the second stopper, and/or the third stopper may be movableinside the cartridge compartment towards the cartridge outlet, e.g. in afirst stopper direction, such as towards the first cartridge end. Forexample, the medicament may be expelled through the cartridge outletupon movement of the first stopper, the second stopper, and/or the thirdstopper, e.g. in the first stopper direction and/or towards thecartridge outlet.

The cartridge may be a dual-chamber cartridge. The cartridge compartmentmay have a first cartridge subcompartment and a second cartridgesubcompartment. The first cartridge subcompartment may be between thefirst stopper and the second stopper. The second cartridgesubcompartment may be between the second stopper and the cartridgeoutlet and/or the third stopper.

The first cartridge subcompartment may contain a first medicamentcomponent of the medicament. The second cartridge subcompartment maycontain a second medicament component of the medicament. Each of thefirst medicament component and/or second medicament component may be apowder composition, a fluid, a liquid, a gel, a gas, and/or anycombination thereof. The first medicament component and/or the secondmedicament component may be solute, such as a powder composition. Thefirst medicament component and/or the second medicament component may bea solvent, such as a fluid composition, such as a liquid composition.The second medicament component may be a powder composition and thefirst medicament component may be a fluid composition, e.g. water orethanol or saline solution or buffer solution or preservative solution.The second medicament component may be a solute. The first medicamentcomponent may be a solvent. It is envisaged that the medicament may beany medicament being injectable via a hypodermic needle, for exampleafter reconstitution of the medicament. The medicament may be a growthhormone. The medicament may be human growth hormone. The medicament maybe a depot version, such as a long-acting version, of human growthhormone. The second medicament component may be a powder composition ofhuman growth hormone.

The cartridge may have a bypass section providing fluid communicationbetween the first cartridge subcompartment and the second cartridgesubcompartment, e.g. when the second stopper is positioned in the bypasssection. The cartridge may have a plurality of bypass sections providingfluid communication between neighbouring cartridge subcompartments, e.g.when a stopper separating the neighbouring cartridge subcompartment ispositioned in the bypass section.

The disclosed auto injector may be a reusable auto injector. A reusableauto injector may be especially useful when the cartridge comprises aplurality of subcompartments. For example an auto injector for a multicompartment or multi chamber cartridge may be more advanced, andtherefore it may be beneficial to allow the auto injector to be usedmore than one time. For example, the auto injector may provide automatedprocesses for mixing medicament components, such as for mixingmedicament components initially provided in different subcompartments ofthe cartridge.

The cartridge may be comprised as part of a cartridge assembly. Thecartridge assembly may comprise the cartridge. Additionally, thecartridge assembly may comprise a needle, such as a needle assemblycomprising a needle, a needle cover, a cartridge holder, and/or acartridge code feature.

The cartridge assembly may comprise the needle, such as the needleassembly comprising the needle. The needle assembly may comprise aneedle cover and/or a needle hub. The cartridge assembly may comprise acartridge holder. The cartridge holder may be configured to engage withthe needle assembly. The cartridge holder may provide for attachment ofthe needle assembly to the cartridge.

The cartridge may comprise a cartridge code feature and/or the cartridgeassembly may comprise the cartridge and the cartridge code feature. Thecartridge code feature may comprise one or more of a colour, a bar code,an RFID tag, an NFC tag, an identification number, and a QR code. Forexample, the cartridge code feature may comprise a colour and/or asequence of colours. The cartridge code feature may be positionedsurrounding or partly surrounding a part of the cartridge compartmentwherein a stopper, such as the first stopper, is initially positioned.Such position of the cartridge code feature may increase readability ofthe cartridge code feature, e.g. since the stopper may form a backgroundfor the cartridge code feature. The stopper, such as the first stoppermay be a light colour, such as light grey or white. The stopper, such asthe first stopper, may be a dark colour, such as dark blue, dark grey,or black. The stopper may form a dark background for the cartridge codefeature. The stopper, such as the first stopper, may reduce reflectionof light, e.g. to further increase readability of the cartridge codefeature.

The cartridge code feature may be positioned at a specific position onthe cartridge, e.g. independently of the stopper(s), such as the firststopper. For example, the cartridge code feature may be positioned at acode distance from the second cartridge end. All cartridges may havetheir cartridge code features positioned at the same position, e.g.positioned at the code distance from the second cartridge end. Suchuniform position of the cartridge code feature may decrease complexity,and decrease size, of the auto injector, as the cartridge code featureis read in the same position for all suitable cartridges.

The cartridge and the cartridge code feature may be manufactured as oneelement. For example, the cartridge code feature may be a certain formof the cartridge. Alternatively, the cartridge code feature may beattached to the cartridge, such as fastened, e.g. by glue, to thecartridge. For example, the cartridge code feature may be a colour codeprinted on the cartridge.

The cartridge code feature may be indicative of one or more cartridgespecifications, such as medicament in the cartridge, concentration ofmedicament in the cartridge, viscosity of medicament in the cartridge,volume and/or mass of medicament in the cartridge, positions ofstopper(s) in the cartridge compartment, etc. The cartridge code featuremay be indicative of a position of the first stopper wherein air in thecartridge compartment is reduced, such as minimized and/or reduced to anamount appropriate for injection. The cartridge code feature may beindicative of the amount of medicament contained in the cartridge. Thecartridge code feature may be indicative of a specific type ofcartridge, such as an ID number of the specific type of cartridge. Theauto injector, such as the processing unit of the auto injector, may beconfigured to determine one or more cartridge specifications based on anID number, e.g. by table lookup. The cartridge code feature may beindicative of a suitable, such as optimal, speed of stopper movement,such as stopper movement in different phases of movement, such as duringmixing, during air-shot, and/or injection. The cartridge code featuremay be indicative of a suitable, such as optimal, speed of movement ofthe first stopper, such as speed of movement of the first stopper indifferent phases of movement, such as during mixing, during air-shot,and/or injection. The cartridge code feature may be indicative of timeneeded for optimal mixing of the first medicament component and thesecond medicament component. The cartridge code feature may beindicative of a suitable dwell time for the medicament, e.g. time toensure that the medicament is distributed into the tissue, e.g.favourable time to wait after injection before retraction of the needle.The cartridge code feature may be indicative of amount of movementenergy needed for optimal mixing of the first medicament component andthe second medicament component. The cartridge code feature may beindicative of desired temperatures of the medicament, e.g. for mixing ofthe first medicament component and the second medicament componentand/or for injection of the medicament.

The auto injector may be a front-loaded auto injector. The auto injectorcomprises a cartridge receiver configured to receive the cartridge. Thecartridge receiver may be configured to receive a cartridge assemblycomprising the cartridge. The cartridge assembly may comprise acartridge holder. The cartridge receiver may have a cartridge receiveropening. The cartridge receiver may be configured to receive thecartridge by insertion of the cartridge, such as the second end of thecartridge, through the cartridge receiver opening. The cartridge may beinserted in a cartridge receiving direction. The cartridge receivingdirection may be opposite the first stopper direction, e.g. when thecartridge is received in the cartridge receiver. The cartridge may be ina first angular position when inserted into the cartridge receiver. Thecartridge may be retained in the cartridge receiver in a second angularposition, e.g. after insertion of the cartridge in the cartridgereceiver.

The cartridge receiver may be configured to receive a cartridge assemblycomprising the cartridge and a cartridge holder. The cartridge assemblymay be retained in the cartridge receiver by one or more cartridgeretention members of the cartridge holder engaging with members of thecartridge receiver.

The cartridge and/or cartridge assembly may be lockable in the cartridgereceiver, e.g. the cartridge and/or cartridge assembly may be locked inthe cartridge receiver to prevent removal of the cartridge and/orcartridge assembly from the cartridge receiver. The cartridge and/orcartridge assembly may be locked in the cartridge receiver by movementof a plunger rod of the auto injector.

The auto injector may comprise a cartridge sensor. The cartridgereceiver may comprise the cartridge sensor. The cartridge sensor may beconfigured to detect reception of the cartridge and/or cartridgeassembly in the cartridge receiver. The cartridge sensor may provide acartridge sensor signal indicative of whether the cartridge and/orcartridge assembly is received in the cartridge receiver. The cartridgesensor may provide a cartridge detection signal indicative of thecartridge and/or cartridge assembly being received in the cartridgereceiver. The cartridge sensor signal may comprise the cartridgedetection signal.

The auto injector may be an electronic auto injector. The auto injectormay comprise a battery. The housing may accommodate the battery. Thebattery may be a rechargeable battery. For example, the battery may be aLi-ion battery or a NiCd battery or a NiMH battery. The battery may beconfigured to be charged by connection of a charger.

The auto injector comprises a drive module. The drive module may becoupled to move, such as actuate, such as advance, a plunger rod, suchas between a retracted plunger rod position and an extended plunger rodposition. Movement of the plunger rod may provide the cartridge and/orcartridge assembly to be locked in the cartridge receiver. For example,the cartridge and/or cartridge assembly may be locked in the cartridgereceiver by advancement of the plunger rod from a retracted plunger rodposition.

The drive module may comprise one or more electrical elements. The drivemodule may be configured to receive electrical power from the battery.The drive module may be electrically connected to the battery forreceiving electrical power. The drive module may be accommodated by thehousing. The drive module may comprise a motor, such as anelectro-mechanical motor, such as a DC motor, e.g. a DC motor with orwithout brushes. The drive module may comprise a solenoid motor. Thedrive module may comprise a shape memory metal engine. The drive modulemay comprise an arrangement of springs configured to actuate the plungerrod. The drive module may comprise a pressurized gas configured toactuate the plunger rod.

The auto injector may comprise a plunger rod, such as the plunger rodmovable by the drive module. The plunger rod may be configured to move astopper, such as the first stopper of the cartridge. For example, whenthe plunger rod is moved towards an extended plunger rod position, suchas from the first plunger rod position to the mix plunger rod positionand/or from the mix plunger rod position to the second plunger rodposition, the plunger rod may be configured to move the first stoppertowards the cartridge outlet, such as to mix the two medicamentcomponents and/or to expel medicament from the cartridge compartmentthrough the cartridge outlet and/or to expel air from the cartridgecompartment through the cartridge outlet.

The plunger rod may be moved to the first plunger rod position, such asa pre-mix plunger rod position, such as towards the extended plunger rodposition, such as from a retracted plunger rod position. The firstplunger rod position may be a pre-mix plunger rod position. The pre-mixplunger rod position may be selected to position the first stopper in aposition wherein fluid communication between the first cartridgesubcompartment and the second cartridge subcompartment is not yetestablished.

The plunger rod may be moved to the mix plunger rod position, such astowards the extended plunger rod position, such as from the firstplunger rod position. The mix plunger rod position may be a positionwherein the first medicament component and the second medicamentcomponent are mixed, such as combined. The mix plunger rod position maybe a position wherein the second stopper is positioned in the bypasssection, such as to provide fluid communication between the firstcartridge subcompartment and the second cartridge subcompartment.

The plunger rod may be moved to a second plunger rod position, such astowards the extended plunger rod position, such as from the mix plungerrod position. The second plunger rod position may be a prime plunger rodposition. The prime plunger rod position may be selected to position thefirst stopper in a position wherein air has been expelled from thecartridge compartment. For example, the prime plunger rod position maybe selected to position the first stopper in a position wherein air inthe cartridge compartment is reduced, such as minimized and/or reducedto an amount appropriate for injection.

The plunger rod may be moved to an injection plunger rod position, suchas towards the extended plunger rod position, such as from the secondplunger rod position. The injection plunger rod position may be aposition wherein the medicament has been expelled and/or injected fromthe cartridge compartment. For example, the injection plunger rodposition may be selected to position the first stopper in a positionwherein medicament in the cartridge compartment is reduced, such asminimized, such as in a position close to the cartridge outlet. Theinjection plunger rod position may be the extended plunger rod position.

The plunger rod may be moved towards a retracted plunger rod position,e.g. to the retracted plunger rod position. For example, the plunger rodmay be moved towards the retracted plunger rod position, e.g. to theretracted plunger rod position, after completion of injection, such asfrom the injection plunger rod position and/or the extended plunger rodposition.

The processing unit may be configured to move the plunger rod to the mixplunger rod position, the second plunger rod position, the injectionplunger rod position, the extended plunger rod position and/or theretracted plunger rod position.

The processing unit may be configured to receive a trigger event, andcontrol the drive module to move the plunger rod to the injectionplunger rod position following reception of the trigger event, such asafter completion of movement of the plunger rod to a preceding plungerrod position, such as the second plunger rod position.

The auto injector may comprise an ejection sensor, such as a plunger rodposition sensor. The ejection sensor may be configured to detect theejection, such as the expelling, of medicament and/or air in thecartridge compartment. The ejection sensor may be configured to detectand/or determine the position of the plunger rod and/or the position ofthe first stopper. The ejection sensor may be configured to detectconditions indicative of the position of the plunger rod and/or theposition of the first stopper. The ejection sensor may be configured toprovide an ejection sensor signal. The ejection sensor signal may beindicative of the position of the plunger rod and/or the first stopper.

The ejection sensor may comprise a tachometer, e.g. a tachometer of thedrive module. The tachometer may be configured to count the revolutionsof the drive module, such as a motor of the drive module, such as therevolutions of the drive module from a set point, such as a pointwherein the position of the plunger rod is known, such as the retractedplunger rod position of the plunger rod. The count of revolutions of thedrive module may be used to determine the actual position of the plungerrod, such as the pre-mix plunger rod position, the mix plunger rodposition, the prime plunger rod position, the injection plunger rodposition, the extended plunger rod position and/or the retracted plungerrod position.

The processing unit may be coupled to the ejection sensor, such as tothe tachometer. The processing unit may receive from the ejection sensora first ejection sensor signal, such as a tachometer signal, indicativeof the count of revolutions of the drive module. The processing unit maydetermine the position of the plunger rod based on the first ejectionsensor signal. The processing unit may receive a second ejection sensorsignal, e.g. from the ejection sensor, indicative of the plunger rodbeing in a known position, such as the retracted plunger rod positionand/or the first plunger rod position. The processing unit may determinethe position of the plunger rod based on the first ejection sensorsignal and the second ejection sensor signal.

The cartridge may be lockable in the cartridge receiver, e.g. thecartridge may be locked in the cartridge receiver to prevent removal ofthe cartridge from the cartridge receiver. Movement of the plunger rodtowards the extended plunger rod position may lock the cartridge in thecartridge receiver. For example, movement of the plunger rod to the mixplunger rod position may lock the cartridge in the cartridge receiver.Movement of the plunger rod towards the retracted plunger rod positionmay unlock the cartridge from the cartridge receiver. For example,movement of the plunger rod to the retracted plunger rod position mayunlock the cartridge in the cartridge receiver. The cartridge may belocked in the cartridge receiver when the plunger rod is not in theretracted plunger rod position and/or close to the retracted plunger rodposition. Coupling the position of the plunger rod with the locking ofthe cartridge in the cartridge receiver may provide the advantage thatthe release of the cartridge may be restricted or prevented when theauto injector is active.

The auto injector may comprise an orientation sensor. The orientationsensor may be configured to provide an orientation signal indicative ofthe orientation of the cartridge, e.g. when the cartridge is received inthe cartridge receiver. The orientation signal may be indicative of theorientation of the cartridge relative to gravity, such as relative tothe direction of gravity. The orientation signal may be an accelerationsignal, e.g. a tri-axial acceleration signal. The orientation signal maycomprise acceleration data, e.g. acceleration data in three dimensions.The orientation signal may comprise acceleration data indicative ofacceleration of the device.

The orientation sensor may be configured to detect an orientation of thecartridge and/or an orientation indicative of the orientation of thecartridge, such as an orientation of the auto injector. The detectedorientation may be relative to gravity, such as relative to thedirection of gravity. The orientation sensor may be configured to detectthe direction of gravity, and/or if the direction of gravity is within acertain range of a predetermined direction. The orientation sensor maycomprise an accelerometer. The orientation sensor may comprise aplurality of accelerometers, such as three accelerometers, such as threeaccelerometers arranged to detect acceleration in three dimensions, suchas a three-dimensional accelerometer. The orientation sensor maycomprise a tilt sensor, a tri-axial accelerometer, a single axisaccelerometer, a magnetometer and/or any combination thereof, and theorientation sensor may provide a measure of roll, pitch and azimuth, ameasure of acceleration and/or tilt in one or more directions.

The orientation sensor may be configured to provide dynamic signals,e.g. linear acceleration and/or velocity and/or positional locationand/or additional rotational acceleration and/or rotational velocity inone, two or three dimensions. The orientation sensor may be configuredto provide full inertial sensing for the position and/or movement of thedevice. The processing unit may be configured to transform motionalsensor signals, such as the orientation signal, from one domain intoanother domain, e.g. integration over time of an acceleration signal toderive a velocity signal and/or integration over time to derive aposition signal from a velocity signal etc.

The orientation sensor may be configured to detect if the cartridge isin a predetermined orientation. The orientation sensor may be configuredto detect if the orientation of the auto injector is indicative of thecartridge being in the predetermined orientation. The predeterminedorientation may be a vertical orientation. The predetermined orientationmay be an orientation within 45 degrees of vertical, such as within 30degrees of vertical. The predetermined orientation may be an orientationwherein the cartridge is orientated such that a longitudinal axis of thecartridge is within 45 degrees of vertical, such as within 30 degrees ofvertical, and wherein the cartridge outlet is above the cartridgecompartment, such as in a vertical position above the cartridgecompartment.

The processing unit may be coupled to the orientation sensor. Theprocessing unit may be configured to receive the orientation signal,e.g. indicative of the orientation of the cartridge, e.g. when thecartridge is received in the cartridge receiver, and/or indicative ofthe orientation of the auto injector.

Movement of the plunger rod to the mix plunger rod position and/or tothe second plunger rod position and/or to the injection plunger rodposition may be based on the orientation of the cartridge, e.g. on theorientation signal. For example, movement of the plunger rod from thefirst plunger rod position to the mix plunger rod position may be basedon the orientation signal.

For example, movement of the plunger rod to the mix plunger rod positionand/or to the second plunger rod position and/or to the injectionplunger rod position may require that a tilt angle between vertical anda longitudinal axis extending along the cartridge is within 45 degrees,such as within 30 degrees, and/or that the cartridge outlet is in avertical position above the cartridge compartment.

Control of the drive module to move the plunger rod to the mix plungerrod position and/or to the prime plunger rod position and/or to theinjection plunger rod position may be based on the orientation of thecartridge, e.g. on the orientation signal.

The processing unit may be configured to control the drive module basedon the orientation signal. For example, the processing unit may beconfigured to control the drive module to move the plunger rod to themix plunger rod position and/or to the second plunger rod positionand/or to the injection plunger rod position based on the orientationsignal. For example, the processing unit may be configured to controlthe drive module to move the plunger rod to the mix plunger rod positionand/or to the second plunger rod position and/or to the injectionplunger rod position only if the orientation signal indicates that atilt angle between vertical and a longitudinal axis extending along thecartridge is within 45 degrees, such as within 30 degrees, of vertical,and/or if the cartridge outlet is in a vertical position above thecartridge compartment.

A first movement parameter may be determined, e.g. based on theorientation signal. The processing unit may be configured to determinethe first movement parameter. The first movement parameter may be basedon cumulative movement of the auto injector. The first movementparameter may be indicative of an amount of movement of the autoinjector during a set period of time, such as since completion ofmovement of the plunger rod to the mix plunger rod position, and/or apreceding predetermined time, such as the preceding 1 second. The firstmovement parameter may be based on a cumulative measure of theorientation signal over time, e.g. since completion of movement of theplunger rod to the mix plunger rod position, and/or a precedingpredetermined time, such as the preceding 1 second. The first movementparameter may be indicative of the device being shaken. Shaking thedevice while the two medicament components are mixing may provide excessfoaming of the medicament.

Excess foaming of the medicament may necessitate an increasedreconstitution time. To prevent foaming, the speed of movement of theplunger rod may be adjusted, e.g. decreased if shaking the device isdetected. Conversely, shaking the device gently might speed up thereconstitution without foaming thereby decreasing the necessaryreconstitution time. Thus, the amount of shaking may influence thedetermined reconstitution time.

Alternatively or additionally, the first movement parameter may beindicative of the auto injector being rotated, e.g. from one verticalorientation, such as wherein a first end of the auto injector, such as adistal end of the auto injector, points substantially upwards, to aninverted orientation wherein the first end of the auto injector pointssubstantially downwards. The first movement parameter may be indicativeof number of inversions of the auto injector. The processing unit may beconfigured to detect and/or count number of inversions. An inversion maycomprise inversion of the auto injector from an orientation wherein thefirst end of the auto injector points substantially upwards, to aninverted orientation wherein the first end of the auto injector pointssubstantially downwards. For example, an inversion may compriseinversion of the auto injector from an orientation wherein the first endof the auto injector points within 45 degrees of upwards, to an invertedorientation wherein the first end of the auto injector points within 45degrees of downwards. Alternatively or additionally, an inversion maycomprise inversion of the auto injector from an orientation wherein thefirst end of the auto injector points substantially downwards, to aninverted orientation wherein the first end of the auto injector pointssubstantially upwards. For example, an inversion may comprise inversionof the auto injector from an orientation wherein the first end of theauto injector points within 45 degrees of downwards, to an invertedorientation wherein the first end of the auto injector points within 45degrees of upwards

The processing unit may be configured to provide feedback, such as viathe user interface of the auto injector, when a predefined number ofinversions have been completed. The reconstitution time may be based onthe first movement parameter, such as if the predefined number ofinversions have been completed. The predefined number of inversions maybe based on an amount of motion energy applied to the mixed drug duringreconstitution, e.g. the predefined number of inversions may becorrelated with the amount of motion energy applied to the mixed drugduring reconstitution. The predefined number of inversions may bebetween 1 and 10, such as between 3 and 7, such as 5. The predefinednumber of inversions may be based on the cartridge code feature, such ason a code signal indicative of the cartridge code feature. Alternativelyor additionally, the predefined number of inversions may be based ontemperature of the medicament, such as a temperature signal indicativeof the temperature of the medicament.

The first movement parameter may be indicative of a combined rotationbetween opposite vertical orientations in combination with the angularspeed of rotation and/or a waiting period/delay between such inversions.The processing unit may, e.g. in addition to counting number ofinversions, measure rotational acceleration of the auto injector. Theprocessing unit may estimate force and energy acting on the drug to bereconstituted, e.g. based on the measure of rotational acceleration ofthe auto injector and/or counting number of inversions. The processingunit may provide feedback, e.g. via the user interface, when apredefined amount of energy has been applied to the auto injector and/orthe cartridge.

Alternatively or additionally, it may be monitored that the accelerationdoes not exceed a predefined upper threshold. The predefined upperthreshold may be indicative of accelerations known to be associated withrisk of foaming. For example, accelerations above the predefined upperthreshold may be known to be associated with risk of foaming.

The total amount of energy applied to the auto injector, such as basedon the measure of rotational acceleration of the auto injector and/orcounting number of inversions, may be assessed continuously to givereal-time instructions e.g. to a user performing such movement, if theenergy level is considered too low, e.g. below a predefined lowerthreshold, and/or if the energy level is considered to high, e.g. abovea predefined upper threshold. The predefined lower threshold may be anenergy level where the movement is considered to have no effect inspeeding up reconstitution. The predefined upper threshold may be anenergy level where the movement is considered to increase the risk offoaming.

The first movement parameter may be indicative of a frequency ofmovement of the auto injector, such as number of inversions per second.

The reconstitution time may be based on the first movement parameter,such as if the first movement parameter is indicative of a frequencyabove a frequency threshold. The frequency threshold may be between0.3-1.2 Hz, such as between 0.5-0.9 Hz, such as 0.7 Hz. The frequencythreshold may be based on the cartridge code feature, such as on a codesignal indicative of the cartridge code feature. Alternatively oradditionally, the frequency threshold may be based on temperature of themedicament, such as a temperature signal indicative of the temperatureof the medicament.

The reconstitution time may be based on the first movement parameter,such as if the predefined number of inversions have been completed, suchas if the predefined number of inversions have been completed with afrequency above the frequency threshold. For example, the reconstitutiontime may be based on the predefined number of inversions being completedat a frequency above the frequency threshold, such as 5 inversions beingcompleted with a frequency of 0.5 Hz or more.

The auto injector, e.g. the cartridge receiver, may be configured toreceive a cartridge assembly comprising the cartridge and a cartridgecode feature.

The auto injector may comprise a code sensor. The code sensor may beconfigured to read a cartridge code feature, such as the cartridge codefeature of the cartridge and/or the cartridge assembly e.g. indicativeof one or more cartridge specifications. The code sensor may beconfigured to provide a code signal indicative of the cartridge codefeature.

The processing unit may be coupled to the code sensor. The processingunit may be configured to receive the code signal. The processing unitmay be configured to receive from the code sensor a code signalindicative of the cartridge code feature. The movement of the plungerrod, such as the movement from the first plunger rod position to the mixplunger rod position, may be based on the code signal.

The processing unit may be configured to determine an unauthorizedcartridge, such as a counterfeit cartridge and/or a used cartridge,and/or a tampered cartridge, and/or a cartridge containing a wrong dose,and/or a cartridge containing a wrong medicament, based on the codesignal.

The code sensor may comprise an optical sensor. The code sensor maycomprise an optical sensor comprising a transmitter and a receiver, suchas a light transmitter and a light receiver. The code sensor may beconfigured to read the cartridge code feature. The code sensor may beconfigured to read colour codes, bar codes, RFID tags, NFC tags,identification numbers, QR codes, and/or any combination hereof.

Movement of the plunger rod, such as positions, speed and/or delays, maybe based on the code signal. For example, movement of the plunger rod tothe mix plunger rod position and/or the second plunger rod positionand/or the injection plunger rod position, may be based on the cartridgecode feature, e.g. on the code signal. For example, control of the drivemodule to move the plunger rod to the mix plunger rod position and/or tothe second plunger rod position may be based on the code signal. Theprocessing unit may be configured to control the drive module based onthe code signal. For example, the processing unit may be configured tocontrol the drive module to move the plunger rod to the mix plunger rodposition and/or to the second plunger rod position based on the codesignal.

Basing the movement of the plunger rod on cartridge specification, e.g.on the code signal, provides that the plunger rod movement may beoptimized to several types of cartridges. For example, the air-shot maybe performed with reduced or no expelling of medicament, therebyincreasing dosage accuracy and/or reducing patient discomfort, e.g. evenwith different cartridges. Additionally or alternatively, the mixingprocedure may be performed with reduced foaming by knowing thespecifications of the cartridge.

Basing the movement of the plunger rod on cartridge specification, e.g.on the code signal, provides that the plunger rod movement may beoptimized to several types of cartridges. For example, the plunger rodmay be kept in a mix plunger rod position for a time depending on thecartridge specification following detection of the cartridge beingreceived in the cartridge receiver and reception of the first inputsignal thereby ensuring appropriate mixing and/or reducing patientdiscomfort, e.g. even with different cartridges.

The auto injector may comprise a resistance sensor. The resistancesensor may be configured to provide a resistance signal. The resistancesignal may be indicative of resistance against movement of the plungerrod. The processing unit may be coupled to the resistance sensor. Theprocessing unit may be configured to receive the resistance signal.

The resistance signal may be indicative of resistance against movementof the plunger rod in one direction, such as movement towards theextended plunger rod position. For example, the resistance signal may beindicative of the force necessary to move the plunger rod, e.g. towardsthe extended plunger rod position.

The resistance sensor may be configured to determine electrical powerconsumed by the drive module, e.g. by measuring electrical resistance,electrical current, and/or electrical voltage of the drive module and/ora combination thereof. The resistance sensor may comprise an electricalresistance sensor, an electrical current sensor, and/or an electricalvoltage sensor. The drive module may comprise the resistance sensor.

The resistance sensor may be configured to measure pressure and/or forceapplied to a plunger rod front end of the plunger rod. The plunger rodfront end may be configured to engage with the first stopper of thecartridge. The resistance sensor may be configured to measure pressureand/or force between the plunger rod and the stopper. For example, theresistance sensor may comprise a pressure transducer and/or a forcetransducer on the plunger rod front end. The plunger rod may comprisethe resistance sensor.

Movement of the plunger rod may be based on the resistance signal. Forexample, movement of the plunger rod to the mix plunger rod positionand/or the second plunger rod position and/or the injection plunger rodposition, may be based on resistance against movement of the plungerrod, e.g. on the resistance signal. For example, control of the drivemodule to move the plunger rod to the mix plunger rod position may bebased on the resistance signal. The processing unit may be configured tocontrol the drive module based on the resistance signal. For example,the processing unit may be configured to control the drive module tomove the plunger rod to the mix plunger rod position based on theresistance signal.

The auto injector may comprise a temperature sensor. The temperaturesensor may be configured to provide a temperature signal, such as atemperature signal indicative of the temperature of the auto injectorand/or of the cartridge and/or of the medicament, such as thetemperature of the medicament in the cartridge, e.g. when the cartridgeis received in the cartridge receiver. The temperature sensor maycomprise an infrared sensor, such as an infrared optical sensor. Thetemperature sensor and the code sensor may utilize a common opticalsensor, such as a common optical sensor. Thus, the optical sensor, suchas an infrared optical sensor may be used both to sense temperature andread the cartridge code feature.

The processing unit may be coupled to the temperature sensor. Theprocessing unit may be configured to receive the temperature signal.

Movement of the plunger rod to the mix plunger rod position and/or tothe second plunger rod position and/or to the injection plunger rodposition may be based on the temperature of the auto injector and/or ofthe cartridge and/or of the medicament. Movement of the plunger rod tothe mix plunger rod position and/or to the second plunger rod positionand/or to the injection plunger rod position may be based on thetemperature signal.

The auto injector, such as the processing unit, may be configured tocontrol the drive module based on the temperature signal. For example,the processing unit may be configured to control the drive module tomove the plunger rod to the mix plunger rod position and/or to the primeplunger rod position and/or to the injection plunger rod position basedon the temperature signal.

The auto injector may comprise a temperature control unit. Thetemperature control unit may be configured to alter the temperature ofthe cartridge, e.g. when the cartridge is received in the cartridgereceiver. The temperature control unit may be configured to raise and/orlower the temperature of the cartridge and/or of the medicament. Thesteps of the procedure being dependent on temperature may thereby becontrolled, for example, in order to perform the steps faster.

The temperature control unit may comprise a heating element. The heatingelement may be configured to raise the temperature of the auto injectorand/or of the cartridge and/or of the medicament. The heating elementmay be a resistive heating element. The heating element may be a lightsource, e.g. an infrared lamp. The heating element may be a dielectricheating element. The heating element may be a thermoelectric element,such as a Peltier element.

The temperature control unit may comprise a cooling element. The coolingelement may be configured to lower the temperature of the auto injectorand/or of the cartridge and/or of the medicament. The cooling elementmay be a thermoelectric element, such as a Peltier element.

The temperature control unit may comprise a thermoelectric element, suchas a Peltier element. The thermoelectric element may be used to raise orlower the temperature, such as by use of the Peltier effect, such as totransfer heat from one side of the element to the other with consumptionof electrical energy. The thermoelectric element may be used to raise orlower the temperature depending on the direction of the current.

The temperature control unit may comprise a contact element configuredto be in contact with the cartridge, e.g. when the cartridge is receivedin the cartridge receiver. The temperature control unit may comprise acoil element. The coil element may be configured to surround an entireperimeter of the cartridge, e.g. when the cartridge is received in thecartridge receiver.

The auto injector may comprise an input device, such as a first inputdevice. The first input device may be a button or a touch sensitive areaor a microphone. The first input device may be configured to provide thefirst input signal. The first input signal may be indicative of a firstuser interaction with the first input device. The first input device maybe configured to provide a second input signal. The second input signalmay be indicative of a second user interaction with the first inputdevice.

The processing unit may be coupled to the first input device. Theprocessing unit may be configured to receive the first input signaland/or the second input signal. The processing unit may be configured tocontrol the drive module to move the plunger rod to the mix plunger rodposition only after receiving the first input signal. The processingunit may be configured to control the drive module to move the plungerrod to the second plunger rod position only after receiving the secondinput signal.

The auto injector may comprise a contact member. The contact member maybe configured to be pressed against the injection site. The contactmember may be movable between an extended contact member position and aretracted contact member position. The contact member may be biasedtowards the extended contact member position, e.g. by a contact memberspring. The contact member may be configured to be moved towards theretracted contact member position, e.g. when pressed against theinjection site. The contact member and/or a contact member sensor may beconfigured to provide a contact member signal indicative of position ofthe contact member. The auto injector and/or the contact member maycomprise a contact member sensor configured to detect the position ofthe contact member. The contact member sensor may be configured toprovide the contact member signal indicative of the contact member.

The contact member may be in a first contact member position, e.g.between the extended contact member position and the retracted contactmember position. The contact member being in the first contact memberposition may indicate that the contact member is close to the retractedcontact member position. The contact member being in the first contactmember position may indicate that the contact member is pressed againstthe injection site. The contact member being in the first contact memberposition may indicate that a needle positioned on the cartridge ispressed sufficiently into the skin for injection of the medicament tostart.

The processing unit may be coupled to the contact member. The processingunit may be configured to receive the contact member signal. The triggerevent may comprise the contact member signal being indicative of thecontact member being in a first contact member position. The contactmember may be a trigger member.

A plunger rod position, such as the first plunger rod position, the mixplunger rod position, the second plunger rod position and/or theinjection plunger rod position may be based on the temperature of themedicament, such as on the temperature signal. For example, themedicament may have slightly different volume at different temperatures,which may be accounted for by determining plunger rod positions based onthe temperature of the medicament. For example, the processing unit maybe configured to determine the plunger rod positions, such as the firstplunger rod position, the mix plunger rod position, the second plungerrod position and/or the injection plunger rod position based on thetemperature signal.

The plunger rod positions, such as the first plunger rod position, themix plunger rod position, the second plunger rod position and/or theinjection plunger rod position may be based on a cartridgespecification, such as on the cartridge code feature, such as on thecode signal. For example, the processing unit may be configured todetermine the plunger rod positions, such as the first plunger rodposition, the mix plunger rod position, the second plunger rod positionand/or the injection plunger rod position based on the code signal.

The plunger rod positions, such as the first plunger rod position, themix plunger rod position, the second plunger rod position and/or theinjection plunger rod position may be based on orientation of thecartridge, such as on orientation signal. For example, the processingunit may be configured to determine the plunger rod positions, such asthe first plunger rod position, the mix plunger rod position, the secondplunger rod position and/or the injection plunger rod position based onthe orientation signal.

The plunger rod positions, such as the first plunger rod position, themix plunger rod position, the second plunger rod position and/or theinjection plunger rod position may be based on shaking of the device,such as on the first movement parameter. For example, the processingunit may be configured to determine the plunger rod positions, such asthe first plunger rod position, the mix plunger rod position, the secondplunger rod position and/or the injection plunger rod position based onthe first movement parameter.

The plunger rod positions, such as the first plunger rod position, themix plunger rod position, the second plunger rod position and/or theinjection plunger rod position may be based on resistance againstmovement of the plunger rod, such as on the resistance signal. Forexample, the processing unit may be configured to determine the plungerrod positions, such as the first plunger rod position, the mix plungerrod position, the second plunger rod position and/or the injectionplunger rod position based on the resistance signal.

The processing unit may be configured to determine the plunger rodpositions, such as the first plunger rod position, the mix plunger rodposition, the second plunger rod position and/or the injection plungerrod position, based on the code signal and/or the temperature signaland/or the orientation signal and/or the first movement parameter and/orthe resistance signal.

Movement of the plunger rod may comprise movement having a plunger rodspeed, such as the mix plunger rod speed, a second plunger rod speedand/or an injection plunger rod speed. The plunger rod speed may bebased on the position of the plunger rod. The plunger rod may be movedto the mix plunger rod position, such as from the first plunger rodposition, with a mix plunger rod speed. The plunger rod may be moved tothe second plunger rod position, such as from the mix plunger rodposition, with a second plunger rod speed. The plunger rod may be movedto the injection plunger rod position, such as from the mix plunger rodposition and/or from the second plunger rod position, with an injectionplunger rod speed.

The plunger rod speed, such as the mix plunger rod speed, the secondplunger rod speed, and/or the injection plunger rod speed may beconstant. The plunger rod speed, such as the mix plunger rod speed, thesecond plunger rod speed, and/or the injection plunger rod speed may bevarying, e.g. varying over time and/or over distance.

The mix-plunger rod speed may be between 1 mm/second and 3 mm/second,such as 1.7 mm/second.

The processing unit may be configured to control the drive module tomove the plunger rod to the mix plunger rod position, such as from thefirst plunger rod position, with the mix plunger rod speed. Theprocessing unit may be configured to control the drive module to movethe plunger rod to the second plunger rod position, such as from the mixplunger rod position, with the second plunger rod speed. The processingunit may be configured to control the drive module to move the plungerrod to the injection plunger rod position, such as from the secondplunger rod position, with the injection plunger rod speed.

The mix plunger rod speed, the second plunger rod speed, and/or theinjection plunger rod speed, may be based on a cartridge specification,such as on the cartridge code feature, such as on the code signal. Theprocessing unit may be configured to determine the mix plunger rodspeed, the second plunger rod speed, and/or the injection plunger rodspeed, based on the code signal.

The mix plunger rod speed, the second plunger rod speed, and/or theinjection plunger rod speed, may be based on the temperature of themedicament, such as on the temperature signal. The processing unit maybe configured to determine the mix plunger rod speed, the second plungerrod speed, and/or the injection plunger rod speed, based on thetemperature signal.

The mix plunger rod speed, the second plunger rod speed, and/or theinjection plunger rod speed, may be based on the orientation of thecartridge, such as on the orientation signal. The processing unit may beconfigured to determine the mix plunger rod speed, the second plungerrod speed, and/or the injection plunger rod speed, based on theorientation signal.

The mix plunger rod speed, the second plunger rod speed, and/or theinjection plunger rod speed, may be based on the first movementparameter. The processing unit may be configured to determine the mixplunger rod speed, the second plunger rod speed, and/or the injectionplunger rod speed, based on the first movement parameter.

The mix plunger rod speed, the second plunger rod speed, and/or theinjection plunger rod speed, may be based on resistance against movementof the plunger rod, such as on the resistance signal. The processingunit may be configured to determine the mix plunger rod speed, thesecond plunger rod speed, and/or the injection plunger rod speed, basedon the resistance signal.

The processing unit may be configured to determine the mix plunger rodspeed, the second plunger rod speed, and/or the injection plunger rodspeed, based on the code signal and/or the temperature signal and/or theorientation signal and/or the first movement parameter and/or theresistance signal.

Movements of the plunger rod, such as movement to the mix plunger rodposition, to the second plunger rod position, to the injection plungerrod position, may be preceded by one or more elapsed time, such asdelays. For example, movement of the plunger rod to the second plungerrod position may require that a reconstitution time has elapsed sincecompletion of the movement of the plunger rod to the mix plunger rodposition. The reconstitution time may be chosen to allow sufficient timeto ensure that the medicament is reconstituted, e.g. that the firstmedicament component and second medicament component has beensufficiently mixed, such as dissolved.

In some circumstances the reconstitution time may be very small. Thereconstitution time may be less than 10 seconds, such as less than 5seconds, such as less than 1 second. Alternatively, the reconstitutiontime may be more than 1 second, such as more than 10 seconds, such asmore than 1 minute, such as more than 5 minutes.

The reconstitution time may be between 1-10 minutes, such as between 2-5minutes, such as 3 minutes.

The processing unit may be configured to control the drive module tomove the plunger rod to the mix plunger rod position and/or the secondplunger rod position and/or to the injection plunger rod position basedon the one or more elapsed time, such as delay times. For example, theprocessing unit may be configured to control the drive module to movethe plunger rod to the second plunger rod position only after thereconstitution time has elapsed since completion of the movement of theplunger rod to the mix plunger rod position.

The reconstitution time may be based on a cartridge specification, e.g.the reconstitution time may be based on the cartridge code feature, e.g.the reconstitution time may be based on the code signal. The processingunit may be configured to determine the reconstitution time based on thecode signal.

Alternatively or additionally, the reconstitution time may be based on atemperature, e.g. the reconstitution time may be based on thetemperature of the medicament, e.g. the reconstitution time may be basedon the temperature signal. For example, the reconstitution time may belonger for lower temperatures than for higher temperatures. Theprocessing unit may be configured to determine the reconstitution timebased on the temperature signal.

Alternatively or additionally, the reconstitution time may be based onthe orientation signal. The processing unit may be configured todetermine the reconstitution time based on the orientation signal.

Alternatively or additionally, the reconstitution time may be based onthe first movement parameter. The processing unit may be configured todetermine the reconstitution time based on the first movement parameter.

Alternatively or additionally, the reconstitution time may be based onresistance against movement of the plunger rod, such as on theresistance signal. The processing unit may be configured to determinethe reconstitution time based on the resistance signal.

The processing unit may be configured to determine the reconstitutiontime based on the code signal and/or the temperature signal and/or theorientation signal and/or the first movement parameter and/or theresistance signal.

The plunger rod may be moved towards the retracted plunger rod position,such as to the retracted plunger rod position, following completion ofthe movement of the plunger rod to the injection plunger rod position.The processing unit may be configured to control the drive module tomove the plunger rod towards the retracted plunger rod positionfollowing completion of the movement of the plunger rod to the injectionplunger rod position.

Movement of the plunger rod towards the retracted plunger rod position,such as to the retracted plunger rod position, such as after completionof the movement of the plunger rod to the injection plunger rodposition, may require that a dwell time has elapsed, e.g. sincecompletion of the movement of the plunger rod to the injection plungerrod position. The dwell time may be chosen to allow sufficient time toensure that the medicament is distributed into the tissue. The dwelltime may be influenced by the medicament and/or concentration of themedicament and/or the amount of medicament and/or the temperature of themedicament. The dwell time may be based on a cartridge specification,e.g. the dwell time may be based on the cartridge code feature, e.g. thedwell time may be based on the code signal. The dwell time may be basedon the temperature of the medicament, e.g. the dwell time may be basedon the temperature signal.

The processing unit may be configured to control the drive module tomove the plunger rod towards the retracted plunger rod position onlyafter the dwell time has elapsed since completion of the movement of theplunger rod to the injection plunger rod position.

The dwell time may be based on a cartridge specification, e.g. the dwelltime may be based on the cartridge code feature, e.g. the dwell time maybe based on the code signal. The processing unit may be configured todetermine the dwell time based on the code signal.

Alternatively or additionally, the dwell time may be based on atemperature, e.g. the dwell time may be based on the temperature of themedicament, e.g. the dwell time may be based on the temperature signal.For example, the dwell time may be longer for lower temperatures thanfor higher temperatures. The processing unit may be configured todetermine the dwell time based on the temperature signal.

Alternatively or additionally, the dwell time may be based on theorientation signal. The processing unit may be configured to determinethe dwell time based on the orientation signal.

Alternatively or additionally, the dwell time may be based on the firstmovement parameter. The processing unit may be configured to determinethe dwell time based on the first movement parameter.

Alternatively or additionally, the dwell time may be based on resistanceagainst movement of the plunger rod, such as on the resistance signal.The processing unit may be configured to determine the dwell time basedon the resistance signal.

The processing unit may be configured to determine the dwell time basedon the code signal and/or the temperature signal and/or the orientationsignal and/or the first movement parameter and/or the resistance signal.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other features and advantages of the present inventionwill become readily apparent to those skilled in the art by thefollowing detailed description of exemplary embodiments thereof withreference to the attached drawings, in which:

FIG. 1 illustrates an exemplary auto injector;

FIG. 2 illustrates an exemplary auto injector with a cartridge;

FIG. 3 schematically illustrates an exemplary cartridge;

FIG. 4 a-d schematically illustrate an exemplary cartridge assembly withexemplary cartridge code features;

FIG. 5 schematically illustrates an exemplary auto injector with acartridge assembly;

FIG. 6 a-d schematically illustrate an auto injector and a cartridgeassembly;

FIG. 7 shows a block diagram of an exemplary auto injector;

FIG. 8 a-f schematically illustrate an exemplary cartridge assembly anda plunger rod in exemplary positions;

FIG. 9 shows an exemplary graph of resistance vs. position;

FIG. 10 shows a flow chart of an exemplary method;

FIG. 11 shows a flow chart of an exemplary method;

FIG. 12 shows a flow chart of an exemplary method;

FIG. 13 a-d schematically illustrate an exemplary user interface; and

FIG. 14 a-c schematically illustrate an exemplary movement of anexemplary auto injector.

DETAILED DESCRIPTION

Various embodiments are described hereinafter with reference to thefigures. Like reference numerals refer to like elements throughout. Likeelements will, thus, not be described in detail with respect to thedescription of each figure. It should also be noted that the figures areonly intended to facilitate the description of the embodiments. They arenot intended as an exhaustive description of the claimed invention or asa limitation on the scope of the claimed invention. In addition, anillustrated embodiment needs not have all the aspects or advantagesshown. An aspect or an advantage described in conjunction with aparticular embodiment is not necessarily limited to that embodiment andcan be practiced in any other embodiments even if not so illustrated, orif not so explicitly described.

FIG. 1 illustrates an exemplary auto injector 4. The auto injector 4 maybe configured for administering a medicament. The auto injector 4 may bean electronic auto injector.

The auto injector 4 comprises a housing 6. The auto injector 4 comprisesa cartridge receiver 300. The cartridge receiver is configured toreceive a cartridge and/or a cartridge assembly comprising a cartridge.The cartridge may contain the medicament.

The cartridge receiver 300 has a cartridge receiver opening 301. Thecartridge receiver 300 is configured to receive the cartridge and/or thecartridge assembly through the cartridge receiver opening 301 in acartridge receiving direction 304 along a longitudinal axis L.

The auto injector 4 may comprise a user interface 1100, as illustrated.The auto injector 4 comprises a trigger member, such as the contactmember 1102. The contact member 1102 may be configured to be pressedagainst an injection site. The contact member 1102 may be movable in thecartridge receiving direction 304, relative to the housing, if pressedagainst the injection site. The contact member 1102 may be part of theuser interface 1100.

The user interface 1100 may comprise a first input member 1108 asillustrated, e.g. a button. The first input member 1108 may provide fora user input from a user. For example, the first input member 1108 maybe used for receiving a push from a user to proceed to a next step.

The user interface 1100 may comprise a first output member 1110 asillustrated, e.g. a plurality of LEDs. The first output member 1110 mayprovide for a user output to a user. The user interface 1100 maycomprise a second output member (not shown), e.g. a speaker. The secondoutput member may be configured to provide audible output to the user.For example, the first output member 1110 and/or the second outputmember may be used to indicate a step in the procedure to the userand/or to indicate an error message.

FIG. 2 illustrates an exemplary system 2. The system 2 comprises an autoinjector 4, as described in relation to FIG. 1, and an exemplarycartridge 700 received in the cartridge receiver 300. The cartridge 700is shown with a needle cover 908. The needle cover 908 extending out ofthe contact member 1102 to allow removal of the needle cover 908 fromthe cartridge 700.

FIG. 3 schematically illustrates an exemplary cartridge 700, such as acartridge 700 being configured to be received in the cartridge receiverof an auto injector, such as the auto injector described in relation toprevious figures.

The cartridge 700 comprises a cartridge compartment 702. The cartridgecompartment 702 may be configured for containing a medicament. Thecartridge 700 has a first end 718 and a second end 720. The cartridge700 comprises a cartridge outlet 714 at the first cartridge end 718. Thecartridge may be configured to expel medicament through the cartridgeoutlet 714.

The cartridge comprises a first stopper 708 movable inside the cartridgecompartment, e.g. in a first stopper direction 722, e.g. towards thefirst cartridge end. For example, the medicament may be expelled throughthe cartridge outlet 714 upon movement of the first stopper 708 in thefirst stopper direction. The cartridge comprises a cartridge back face716 at the second cartridge end. The cartridge back face 716 comprises acartridge back end opening for providing access to the first stopper 708for a plunger rod.

As illustrated, the cartridge 700 may be a dual chamber cartridge. Thecartridge comprises a second stopper 710 movable inside the cartridgecompartment 702, e.g. in the first stopper direction 722, e.g. towardsthe first cartridge end. The cartridge compartment 702 comprises a firstcartridge subcompartment 704 and a second cartridge subcompartment 706.The first cartridge subcompartment 704 is between the first stopper 708and the second stopper 710. The second cartridge subcompartment 706 isbetween the second stopper 710 and the cartridge outlet 714. Thecartridge comprises a bypass section 712 for providing fluidcommunication between the first cartridge subcompartment and the secondcartridge subcompartment. The bypass section 712 provides fluidcommunication between the first cartridge subcompartment and the secondcartridge subcompartment when the second stopper 710 is positioned inthe bypass section 712.

The first cartridge subcompartment 704 contains a first medicamentcomponent 792 of the medicament 790. The first medicament component 792may be a liquid as illustrated. The second cartridge subcompartment 706contains a second medicament component 794 of the medicament 790. Thesecond medicament component 794 may be a powder composition. Bypositioning of the second stopper 710 within the bypass section 712, thefirst medicament component 792 may be transmitted into the secondcartridge subcompartment 706 via the bypass section 712, thereby mixingthe first medicament component 792 and the second medicament component794 to achieve the combined medicament 790.

FIGS. 4a-d schematically illustrates an exemplary cartridge assembly600. The cartridge assembly 600 comprises an exemplary cartridge 700 andan exemplary cartridge code feature 1000. The cartridge 700 has a firstcartridge end 718 and a second cartridge end 720. The first stopperdirection 722 is from the second cartridge end 720 to the firstcartridge end 718. The cartridge code feature 1000 is positioned nearthe second cartridge end 720, e.g. closer to the second cartridge end720 than the first cartridge end 718. In another exemplary cartridgeassembly, the cartridge code feature 1000 may be positioned near thefirst cartridge end 720.

FIGS. 4a-d illustrates different types of exemplary cartridge codefeatures 1000.

FIG. 4a illustrates an exemplary cartridge assembly 600, wherein thecartridge code feature 1000 comprises two strips. The two strips may becoloured, e.g. differently coloured. The combination and/or sequence ofcolours may be indicative of a code of the cartridge code feature 1000.

FIG. 4b illustrates an exemplary cartridge assembly 600, wherein thecartridge code feature 1000 comprises bar codes. The cartridge codefeature 1000 may comprise one or more bar codes. The bar code may beindicative of a number indicative of a code of the cartridge codefeature 1000.

FIG. 4c illustrates an exemplary cartridge assembly 600, wherein thecartridge code feature 1000 comprises differently grated strips. Forexample, as illustrated, the cartridge code feature 1000 may comprisetwo strips wherein the first strip is grated at 45 deg., and the secondstrip is grated at −45 deg. The grating, and/or the grating of thestrips relative to each other, may be indicative of a code of thecartridge code feature 1000.

FIG. 4d illustrates an exemplary cartridge assembly 600, wherein thecartridge code feature 1000 comprises an electromagnetically readabletag, such as an RFID tag or an NFC tag. The electromagnetically readabletag may contain data that is indicative of a code of the cartridge codefeature 1000.

FIG. 5 illustrates an exemplary system 2. The system 2 comprises an autoinjector 4, as described, for example, in relation to FIG. 1, and anexemplary cartridge assembly 600. The cartridge assembly 600 comprises acartridge 700 with a cartridge compartment 702, a needle assembly 900,and a cartridge code feature 1000. The cartridge assembly 600 isreceived in the auto injector 4.

The cartridge assembly 600 comprises a cartridge holder 800. Thecartridge holder 800 is configured for retention of the cartridge 700 inthe cartridge receiver 300 of the auto injector 4. The cartridge holder800 comprises a cartridge retention member 808. The cartridge retentionmember 808 engages with the cartridge receiver 300 for reception andretention of the cartridge 700 and the cartridge assembly 600 in thecartridge receiver 300.

The needle assembly 900 comprises a needle 902 and a needle hub 904. Theneedle assembly 900 is attached to the cartridge 700, e.g. by the needlehub 904 having a cartridge holder coupling portion 906, e.g. a threadedcoupling portion, being in engagement with a needle assembly couplingportion 812 of the cartridge holder 800. The needle 902 extends throughthe cartridge outlet 714 of the cartridge 700. The cartridge outlet 714may be blocked by a resilient sealing being penetrated by the needle902, when the needle assembly 900 is attached to the cartridge 700.

The auto injector 4 comprises a code sensor 24 configured to read thecartridge code feature 1000. When the cartridge assembly 600 isinserted, as shown, the cartridge code feature 1000 is lined up with thecode sensor 24.

The auto injector 4 comprises a plunger rod 400. The plunger rod 400 isconfigured to advance a first stopper of the cartridge 700. The plungerrod 400 comprises an outer plunger rod 404 with an inner thread, and aninner plunger rod 402 with an outer thread. The thread of the innerplunger rod 402 is in engagement with the thread of the outer plungerrod 404. The outer plunger rod 404 is prevented from rotating relativeto the housing of the auto injector. The movement of the plunger rod 400comprises rotation of the inner plunger rod 402. The rotation of theinner plunger rod 402 results in translational movement of the outerplunger rod 404, due to the outer plunger rod 404 being rotationallyrestricted. The outer plunger rod 404, when moved translationally in thefirst stopper direction 722, is configured to abut the first stopper ofthe cartridge 700, and to move the first stopper in the first stopperdirection 722.

The drive module 500 is coupled to actuate the plunger rod 400. Thedrive module 500 is electrically connected to a battery for receivingelectrical power. The drive module 500 comprises a motor 502, such as anelectro-mechanical motor, such as a DC motor. The drive module 500comprises a transmission 504 for coupling the motor 502 to the innerplunger rod 402 of the plunger rod 400.

Although the example shown comprises a motor 502, which may be anelectro-mechanical motor, it will be readily understood that the autoinjector 4 may be realised having an alternative drive module, such ascomprising a solenoid motor, a shape memory metal engine, an arrangementof springs and/or a pressurized gas configured to actuate the plungerrod 400.

The auto injector 4 comprises an ejection sensor 26, such as a plungerrod position sensor. The ejection sensor 26 is configured to detect theposition of the plunger rod 400. In the illustrated example, theejection sensor 26 comprises a tachometer configured to count/detect therevolutions of the motor 502. Thus, the position of the plunger rod 400may be determined based on the count of revolutions of the motor 502.The ejection sensor 26 may, based on the detection of the position ofthe plunger rod 400, detect the expelling of medicament and/or air inthe cartridge compartment. The position of the plunger rod 400 may beindicative of the position of the first stopper of the cartridge 700,e.g. the most advanced position of the plunger rod 400, e.g. while thecartridge 700 is in the cartridge receiver 300, may be indicative of theposition of the first stopper of the cartridge 700.

FIGS. 6a-d schematically illustrate an auto injector 4 and a cartridgeassembly 600. FIGS. 6a-d schematically illustrates exemplary positionsof a contact member 1102 of the auto injector 4 in various situations.

The auto injector 4 comprises a cartridge receiver 300 configured forreceiving and retaining a cartridge. The auto injector 4 comprises acontact member 1102. The contact member 1102 may be movable between anextended contact member position and a retracted contact memberposition. The contact member 1102 comprises a contact member protrudingpart 1112. The contact member protruding part 1112 is configured to movewith the contact member 1102. The contact member 1102 may be biased,e.g. by a contact member spring (not shown), towards the extendedcontact member position.

The contact member comprises a needle cover engagement member 1114. Theneedle cover engagement member 1114 is configured to abut a needle coverabutment face, e.g. of a needle cover positioned on the cartridgeinserted into the cartridge receiver 300.

The auto injector 4 comprises a contact member sensor 1104 configured todetect a position of the contact member 1102. The contact member sensor1104 comprises a first contact member sensor 1130 and a second contactmember sensor 1132. The first contact member sensor 1130 and the secondcontact member sensor 1132 may be optical sensors. The contact membersensor 1104 detects the position of the contact member 1102 by thecontact member protruding part 1112 covering the first contact membersensor 1132 when the contact member 1102 is in a first contact memberposition, and the contact member protruding part 1112 covering thesecond contact member sensor 1132 when the contact member 1102 is in asecond contact member position.

The first contact member position may be detected by the first contactmember sensor 1130 being covered and the second contact member sensor1132 being covered. The second contact member position may be detectedby the first contact member sensor 1130 not being covered and the secondcontact member sensor 1132 being covered. The extended contact memberposition may be detected by the first contact member sensor 1130 notbeing covered and the second contact member sensor 1132 not beingcovered.

FIG. 6a schematically illustrates the auto injector 4 with no receivedcartridge and/or cartridge assembly. The contact member 1102 is in theextended contact member position. A cartridge may be inserted into thecartridge receiver 300 in the cartridge receiving direction 322 throughthe contact member 1102 defining a cartridge receiver opening 301.

FIG. 6b schematically illustrates the auto injector 4 with a cartridgeassembly 600 received. The cartridge assembly 600 comprises a cartridge700, a cartridge holder 800 and a needle assembly 900. The needleassembly comprises a needle 902 and a needle cover 908. The needle coverhas a needle cover abutment face 910. The needle cover abutment face 910engages the needle cover engagement member 1114 of the contact member1102. The contact member 1102 is in the second contact member position,e.g. caused by the presence of the needle cover 908 and the abutment ofthe needle cover abutment face 910 on the needle cover engagement member1114. The contact member protruding part 1112 covers the second contactmember sensor 1132. The contact member protruding part 1112 does notcover the first contact member sensor 1130.

FIG. 6c schematically illustrates the auto injector 4 with a cartridgeassembly 600 received. Compared to FIG. 6b , the needle cover 908 hasbeen removed. The contact member 1102 is in the extended contact memberposition. The contact member 1102 is allowed to be moved to the extendedcontact member position since the needle cover abutment face 910 doesnot abut the needle cover engagement member 1114. The contact memberprotruding part 1112 has moved with the contact member 1102. The contactmember protruding part 1112 does not cover the second contact membersensor 1132. The contact member protruding part 1112 does not cover thefirst contact member sensor 1130.

FIG. 6d schematically illustrates the auto injector 4 with a cartridgeassembly 600 received. The contact member 1102 is in the first contactmember position. The first contact member position may be the retractedcontact member position, or close to the retracted contact memberposition. The contact member 1102 may have been moved to the firstcontact member position by the contact member 1102 being pressed againstan injection site, thereby inserting the needle 902 into the injectionsite. The contact member protruding part 1112 has moved with the contactmember 1102. The contact member protruding part 1112 covers the firstcontact member sensor 1130. The contact member protruding part 1112covers the second contact member sensor 1132.

FIG. 7 shows a block diagram of an exemplary auto injector 4. The autoinjector 4 comprises a plurality of sensors 22, 24, 26, 28, 30, 32, 34,a processing unit 20, a drive module 500, a user interface 1100, and atemperature control unit 36. The sensors 22, 24, 26, 28, 30, 32, 34 arecoupled to the processing unit 20. The user interface 1100 is coupled tothe processing unit 20. The processing unit is coupled to the drivemodule 500.

The processing unit 20 receives signals from the sensors 22, 24, 26, 28,30, 32, 34 and the user interface 1100. The processing unit 20 isconfigured to control the drive module 500. The processing unit 20 maycontrol the drive module 500 based on one or more of the receivedsignals from the sensors 22, 24, 26, 28, 30, 32, 34 and the userinterface 1100. The processing unit 20 is configured to provide useroutputs via the user interface 1100. The processing unit 20 isconfigured to control the temperature control unit 36. The processingunit 20 may control temperature control unit 36 based on one or more ofthe received signals from the sensors 22, 24, 26, 28, 30, 32, 34 and theuser interface 1100.

The auto injector 4 comprises an orientation sensor 22. The orientationsensor 22 is configured to provide an orientation signal indicative ofthe orientation of a cartridge received in the auto injector 4. Forexample, the orientation sensor 22 may be configured to detect theorientation of the auto injector 4. The orientation of the cartridge maybe determined based on the orientation of the auto injector 4. Theorientation sensor 22 may be configured to detect the direction ofgravity. For example, the orientation sensor 22 may comprise anaccelerometer.

The processing unit 20 is coupled to the orientation sensor 22. Theprocessing unit 20 is configured to receive the orientation signal. Theprocessing unit 20 may determine the orientation of the cartridge basedon the orientation signal. The processing unit 20 may control the drivemodule 500 based on the orientation signal. For example, the processingunit 20 may be configured to control the drive module 500 to move theplunger rod based on the orientation signal. For example, the processingunit 20 may be configured to control the drive module 500 to move theplunger rod towards the extended plunger rod position, such as to apre-mix plunger rod position and/or a mix plunger rod position and/orthe prime plunger rod position, only if the cartridge outlet is pointingupwards. Alternatively or additionally, the processing unit 20 mayprovide user output via the user interface 1100 based on the orientationsignal.

The auto injector 4 comprises a code sensor 24. The code sensor 24 isconfigured to read a cartridge code feature, and provide a code signalindicative of a cartridge code feature. For example, the code sensor maybe configured to read/detect a colour code.

The processing unit 20 is coupled to the code sensor 24. The processingunit 20 is configured to receive the code signal. The processing unit 20may determine the cartridge code feature of the cartridge assembly basedon the code signal. The processing unit 20 may control the drive module500 based on the code signal. For example, the processing unit 20 may beconfigured to control the drive module 500 to move the plunger rodtowards the extended plunger rod position, such as to the pre-mixplunger rod position and/or the mix plunger rod position and/or theprime plunger rod position and/or the injection plunger rod position,based on the code signal. The processing unit 20 may be configured todetermine a threshold, such as a plunger rod threshold, and/or aresistance threshold, based on the code signal. Alternatively oradditionally, the processing unit 20 may provide user output via theuser interface 1100 based on the code signal.

The auto injector 4 comprises an ejection sensor 26, such as a plungerrod position sensor. The ejection sensor 26 is configured to detect theposition of the plunger rod of the auto injector 4, and provide anejection sensor signal indicative of the position of the plunger rod.The ejection sensor 26 may comprise a tachometer coupled to the drivemodule 500.

The processing unit 20 is coupled to the ejection sensor 26. Theprocessing unit 20 is configured to receive the ejection sensor signal.The processing unit 20 may determine the position of the plunger rodbased on the ejection sensor signal. The processing unit 20 may controlthe drive module 500 based on the ejection sensor signal. For example,the processing unit 20 may be configured to control the drive module 500to start, stop or continue movement of the plunger rod based on theejection sensor signal. For example, the processing unit 20 may beconfigured to determine a present plunger rod position based on theejection sensor signal. The plunger rod being in the pre-mix plunger rodposition and/or the mix plunger rod position and/or the prime plungerrod position and/or the injection plunger rod position may be determinedbased on the ejection sensor signal. Alternatively or additionally, theprocessing unit 20 may provide user output via the user interface 1100based on the ejection sensor signal.

The auto injector 4 comprises a cartridge sensor 28. The cartridgesensor 28 is configured to detect reception of a cartridge assembly inthe auto injector 4. The cartridge sensor 28 provides a cartridge sensorsignal indicative of reception of a cartridge assembly.

The processing unit 20 is coupled to the cartridge sensor 28. Theprocessing unit 20 is configured to receive the cartridge sensor signal.The processing unit 20 may control the drive module 500 based on thecartridge sensor signal. For example, the processing unit 20 may beconfigured to control the drive module 500 to start movement of theplunger rod if a cartridge assembly is received, and/or only if acartridge assembly is received. Alternatively or additionally, theprocessing unit 20 may provide user output via the user interface 1100based on the cartridge sensor signal.

The code sensor 24 and the cartridge sensor 28 may be the same sensor,e.g. the code sensor 24 may be configured to detect reception of acartridge assembly and subsequently read the cartridge code feature.

The auto injector 4 comprises a needle sensor 30. The needle sensor 30is configured to detect a needle, and/or a needle assembly, and/or aneedle cover of a needle assembly, of the cartridge assembly, when thecartridge assembly is received in the auto injector 4. The needle sensor30 provides a needle signal indicative of the presence of a needle,and/or a needle assembly, and/or a needle cover of a needle assembly, ofthe cartridge assembly.

The processing unit 20 is coupled to the needle sensor 30. Theprocessing unit 20 is configured to receive the needle signal. Theprocessing unit 20 may control the drive module 500 based on the needlesignal. For example, the processing unit 20 may be configured to controlthe drive module 500 to start movement of the plunger rod, e.g. towardsthe extended plunger rod position, such as to the pre-mix plunger rodposition and/or the mix plunger rod position and/or the prime plungerrod position and/or the injection plunger rod position, only if a needleis present, and/or only if a needle cover is not present, such asremoved. Detection of a needle cover may be indicative of a needle beingpresent. The processing unit 20 may be configured to control the drivemodule 500 to start only if a needle cover has been detected, andsubsequently is not detected, e.g. it has been removed. Alternatively oradditionally, the processing unit 20 may provide user output via theuser interface 1100 based on the needle signal.

The needle sensor 30 may be part of the contact member sensor, asexemplified in FIG. 6.

The auto injector 4 comprises a temperature sensor 32. The temperaturesensor 32 is configured to detect a temperature, such as a temperatureof the auto injector and/or of the cartridge and/or of the medicament.The temperature sensor 32 is configured to provide a temperature signalindicative of the temperature.

The processing unit 20 is coupled to the temperature sensor 32. Theprocessing unit 20 is configured to receive the temperature signal. Theprocessing unit 20 may be configured to determine the temperature, suchas the temperature of the auto injector and/or of the cartridge and/orof the medicament based on the temperature signal. The processing unit20 may control the drive module 500 based on the temperature signal. Forexample, the processing unit 20 may be configured to control the drivemodule 500 to move the plunger rod towards the extended plunger rodposition, such as to the pre-mix plunger rod position and/or the mixplunger rod position and/or the prime plunger rod position and/or theinjection plunger rod position, based on the temperature signal. Theprocessing unit 20 may determine plunger rod positions based on thetemperature signal. For example, the processing unit 20 may beconfigured to determine the pre-mix plunger rod position and/or the mixplunger rod position and/or the prime plunger rod position and/or theinjection plunger rod position based on the temperature signal.Alternatively or additionally, the processing unit 20 may provide useroutput via the user interface 1100 based on the temperature signal.

The auto injector 4 comprises a resistance sensor 34. The resistancesensor 34 is configured to detect resistance against movement of theplunger rod of the auto injector 4. The resistance sensor 34 may beconfigured to detect resistance against movement of the plunger rodbased on measurements of the drive module 500. For example, theresistance sensor 34 may be configured to detect the electrical currentof a motor of the drive module 500. The resistance sensor 34 isconfigured to provide a resistance signal indicative of resistanceagainst movement of the plunger rod.

The processing unit 20 is coupled to the resistance sensor 34. Theprocessing unit 20 is configured to receive the resistance signal. Theprocessing unit 20 may be configured to determine the resistance againstmovement of the plunger rod based on the resistance signal. Theprocessing unit 20 may control the drive module 500 based on theresistance signal. For example, the processing unit 20 may be configuredto control the drive module 500 to adjust movement of the plunger rodbased on the resistance signal. For example, the processing unit 20 maybe configured to control the drive module 500 to start, stop or continuemovement of the plunger rod based on the resistance signal.Alternatively or additionally, the processing unit 20 may provide useroutput via the user interface 1100 based on the resistance signal.

The auto injector 4 comprises a temperature control unit 36. Thetemperature control unit 36 is configured to detect configured to alterthe temperature, such as a temperature of the auto injector and/or ofthe cartridge and/or of the medicament, e.g. based on the temperature ofthe auto injector and/or of the cartridge and/or of the medicament, suchas on the temperature signal. For example, the temperature control unit36 is configured to alter the temperature of the cartridge when receivedin the cartridge receiver.

The processing unit 20 is coupled to the temperature control unit 36.The processing unit 20 is configured to control the temperature controlunit 36. The processing unit 20 may be configured to alter thetemperature, such as the temperature of the auto injector and/or of thecartridge and/or of the medicament, e.g. based on the temperaturesignal. For example, the processing unit 20 may be configured to controlthe temperature control unit 36 to raise the temperature of the autoinjector and/or of the cartridge and/or of the medicament, based on thetemperature signal.

The temperature control unit 36 may comprise a heating element 38. Theheating element 38 may be configured to raise the temperature of theauto injector and/or of the cartridge and/or of the medicament. Theheating element 38 may be a resistive heating element. The heatingelement 38 may be a dielectric heating element.

The temperature control unit 36 may comprise a cooling element 40. Thecooling element 40 may be configured to lower the temperature of theauto injector and/or of the cartridge and/or of the medicament.

The temperature control unit 36 may comprise a contact element 42. Thecontact element 42 may be configured to be in contact with the cartridgewhen received in the cartridge receiver. The contact element 42 mayprovide an increased heat transfer between the temperature control unit36 and the auto injector and/or the cartridge and/or the medicament.

The temperature control unit 36 may comprise a coil element 44. The coilelement 44 may be configured to surround an entire perimeter of thecartridge when received in the cartridge receiver. The coil element 44may provide an increased heat transfer between the temperature controlunit 36 and the auto injector and/or the cartridge and/or themedicament.

The auto injector 4 is illustrated comprising all of the above mentionedelements. However, alternatively, the auto injector may comprise onlyone or any combination of one or more of the above mentioned elements.

The auto injector comprises a user interface 1100. The user interface1100 may comprise one or more input members, e.g. a first input member,for receiving a user input. The user interface is configured to providea user input signal indicative of the received user input. The userinterface 1100 may provide a first input signal and/or a second inputsignal.

The processing unit 20 is coupled to the user interface 1100. Theprocessing unit 20 is configured to receive the user input signal, suchas the first input signal and/or the second input signal. The processingunit 20 may control the drive module 500 based on the user input signal.For example, the processing unit 20 may be configured to control thedrive module 500 to move the plunger rod towards the extended plungerrod position, such as to the pre-mix plunger rod position and/or the mixplunger rod position and/or the prime plunger rod position and/or theinjection plunger rod, based on the user input signal and/or followingthe user input signal.

The auto injector comprises a housing 6 accommodating the sensors 22,24, 26, 28, 30, 32, 34, processing unit 20, user interface 1100, drivemodule 500, and temperature control unit 36.

FIGS. 8a-f schematically illustrate exemplary cartridge assemblies 600and a plunger rod 400. The cartridge assembly 600 comprises a cartridge700, such as the cartridge described in relation to FIG. 3, a cartridgeholder 800, and a needle assembly 900. For intelligibility, the autoinjector comprising the plunger rod 400 is not shown.

The cartridge holder 800 comprises a cartridge retention member 808. Thecartridge retention member 808 is configured for engagement with acartridge receiver of the auto injector. The cartridge holder 800comprises a needle assembly coupling portion 812. The needle assemblycoupling portion 812 is configured for engagement with a cartridgeholder coupling portion 906 of the needle assembly 900. The needleassembly coupling portion 812 allows attachment of a needle to thecartridge 700.

The needle assembly 900 comprises a needle 902 and a needle hub 904. Theneedle assembly 900 is attached to the cartridge 700, e.g. by the needlehub 904 having a cartridge holder coupling portion 906, e.g. a threadedcoupling portion, being in engagement with a needle assembly couplingportion 812 of the cartridge holder 800. The needle 902 extends throughthe cartridge outlet 714 of the cartridge 700.

FIG. 8a schematically illustrates a situation wherein the plunger rod400 is in an exemplary retracted plunger rod position. The cartridge 700may be a new cartridge. The first stopper 708 is positioned in aninitial position. The second stopper 710 is in an initial position, e.g.behind the bypass section 712, wherein the bypass section 712 does notform a fluid connection between the first subcompartment 704 and thesecond subcompartment 706.

FIG. 8b schematically illustrates a situation wherein the plunger rod400 is in an exemplary pre-mix plunger rod position. Compared to FIG. 8a, the plunger rod 400 is moved towards an extended plunger rod position.A plunger rod front end 410 of the plunger rod 400 abuts the firststopper 708. Thus, the plunger rod 400 has started to move the firststopper 708 in the first stopper direction 722, by movement in the firstplunger rod direction 422. The second stopper 710 is in a position, e.g.behind the bypass section 712, wherein the bypass section 712 does notform a fluid connection between the first subcompartment 704 and thesecond subcompartment 706.

FIG. 8c schematically illustrates a situation wherein the plunger rod400 is in an exemplary position wherein a fluid connection isestablished between the first subcompartment 704 and the secondsubcompartment 706 via the bypass section 712. The plunger rod front end410 of the plunger rod 400 abuts the first stopper 708. The plunger rod400 has moved the first stopper 708 in the first stopper direction 722,by movement in the first plunger rod direction 422. The second stopper710 is in the bypass section 712, wherein the bypass section 712 forms afluid connection between the first subcompartment 704 and the secondsubcompartment 706. Thus, further movement of the first stopper 708 inthe first stopper direction 722, e.g. by movement of the plunger rod 400in the first plunger rod direction 422, will transmit the content of thefirst subcompartment 704, e.g. a first medicament component (not shown)into the second subcompartment 706, e.g. through the bypass section 712.

FIG. 8d schematically illustrates a situation wherein the plunger rod400 is in an exemplary mix plunger rod position. The plunger rod frontend 410 abuts the first stopper 708. The first stopper 708 abuts thesecond stopper 710. The first subcompartment 704 is compressed. Thesecond stopper 710 is in a position after the bypass section 712. Thus,the fluid connection between the first subcompartment 704 and the secondsubcompartment 706 has been closed.

FIG. 8e schematically illustrates a situation wherein the plunger rod400 is in an exemplary prime plunger rod position. Compared to FIG. 8d ,the plunger rod 400 is moved towards an extended plunger rod position,e.g. to expel air from the cartridge compartment 702.

FIG. 8f schematically illustrates a situation wherein the plunger rod400 is in an exemplary injection plunger rod position. For example aftercomplete injection, the plunger rod 400 may be in the injection plungerrod position. The first stopper 708 and the second stopper 710 is in aposition close to the cartridge outlet 714. Contents of the cartridgecomponent, e.g. the medicament, has been expelled, e.g. through thecartridge outlet 714 and/or the needle 902. A residual volume of themedicament may be remaining in the cartridge.

FIG. 9 shows an exemplary trace T of resistance Re against movement ofthe plunger rod dependent on the position P of the plunger rod. Theplunger rod is moved from a retracted plunger rod position PR to anextended plunger rod position PE. In the beginning of the movement, theresistance against movement of the plunger rod is constant Ex1, e.g. theplunger rod does not yet push a stopper. Afterwards, a plunger rod frontend of the plunger rod abuts a first stopper of the cartridge, and theresistance against movement of the plunger rod increases Ex2. Theincreased resistance is caused by the resistance against movement of thefirst stopper, e.g. due to frictional force. The resistance may decreaseslightly after the first stopper has started moving, as illustrated.When the plunger rod approaches the extended plunger rod position PE,the resistance may increase again Ex3, e.g. due to the first stopperapproaching an end of the cartridge.

The trace T is an example of resistance against plunger rod movementwhen the cartridge received is a new and/or unused and/or normalcartridge. Determining a cartridge parameter may be based on theresistance and/or plunger rod position. Determining the cartridgeparameter may be based on one or more thresholds, such as resistancethresholds, such as a low resistance threshold Re1 and/or a highresistance threshold Re2, and/or plunger rod thresholds, such as a firstplunger rod threshold P1 and/or a second plunger rod threshold P2.

Other situations, such as situations wherein the cartridge received isapparently used and/or flawed, are exemplified by additional exemplarytraces, T2, T3, T4.

Trace T2 illustrates an exemplary situation wherein the resistanceagainst movement increases above the low resistance threshold Re1 beforethe plunger rod position has reached the first plunger rod threshold P1.Such situation may for example indicate a flawed cartridge, or thatsomething is blocking the plunger rod from moving. Following suchsituation, the plunger rod may be retracted to the retracted plunger rodposition and an error message may be provided through a user interface.

Trace T3 illustrates an exemplary situation wherein the resistanceagainst movement has not increased above the low resistance thresholdRe1 before the plunger rod position has reached the second plunger rodthreshold P2. Such situation may for example indicate a cartridgewherein the first stopper is in an advanced position, e.g. a usedcartridge. Following such situation, the plunger rod may be retracted tothe retracted plunger rod position and an error message may be providedthrough a user interface.

Trace T4 illustrates an exemplary situation wherein the resistanceagainst movement increases above the high resistance threshold Re2, e.g.after the plunger rod position has passed the first plunger rodthreshold P1. Such situation may for example indicate that the firststopper is blocked from moving, e.g. the cartridge may be flawed.Following such situation, the plunger rod may be retracted to theretracted plunger rod position and an error message may be providedthrough a user interface.

The thresholds, such as the low resistance threshold Re1, the highresistance threshold Re2, the first plunger rod threshold P1, and/or thesecond plunger rod threshold P2 may be individually determined for thecartridge received. For example, the processing unit of the autoinjector may be configured to determine one or more of the thresholds,based on a cartridge code feature of the cartridge and/or cartridgeassembly received.

FIG. 10 shows a flow chart of an exemplary method 6000 for operating anauto injector. The method 6000 comprises: receiving 6002 a temperaturesignal from a temperature sensor indicative of the temperature of themedicament; moving 6004 the plunger rod from a first plunger rodposition to a mix plunger rod position with a mix plunger rod speed;moving 6006 the plunger rod from the mix plunger rod position to asecond plunger rod position after a reconstitution time has elapsedsince completion of movement of the plunger rod to the mix plunger rodposition. The method 6000 may further comprise receiving 6008 a triggerevent; and moving 6010 the plunger rod to an injection plunger rodposition.

The auto injector may comprise a cartridge receiver configured toreceive a cartridge comprising a first stopper and a cartridgecompartment containing the medicament. The cartridge compartment mayhave a first cartridge subcompartment containing a first medicamentcomponent of the medicament and a second cartridge subcompartmentcontaining a second medicament component of the medicament. The autoinjector may further comprise a plunger rod configured to move the firststopper, and the temperature sensor.

The mix plunger rod position may be selected to position the firststopper in a position wherein the first medicament component is mixedwith the second medicament component.

The movement 6004 from the first plunger rod position to the mix plungerrod position may be based on the temperature signal.

The second plunger rod position may be a prime plunger rod position. Theprime plunger rod position may be selected to position the first stopperin a position wherein air in the cartridge compartment is reduced to anamount appropriate for injection.

Moving 6004 the plunger rod to the mix plunger rod position may followdetection of the cartridge being received in the cartridge receiverand/or reception of a first input signal. For example, moving 6004 theplunger rod to the mix plunger rod position may be performed only aftera cartridge is detected and the first input signal is received.

Alternatively or additionally, moving 6004 the plunger rod to the mixplunger rod position may be preceded by determining orientation of thecartridge (as described in more detail in relation to FIG. 12). Forexample, moving 6004 the plunger rod to the mix plunger rod position mayrequire that the outlet of the cartridge is pointing upwards, e.g.determined by determining orientation of the cartridge. Moving 6004 theplunger rod to the mix plunger rod position may be temporary paused ifthe orientation of the cartridge is not within a predefined range oforientations.

Moving 6006 the plunger rod to the second plunger rod position mayrequire that the outlet of the cartridge is pointing upwards, e.g.determined by determining orientation of the cartridge. Moving 6006 theplunger rod to the second plunger rod position may be temporary pausedif the orientation of the cartridge is not within a predefined range oforientations.

Moving 6006 the plunger rod from the mix plunger rod position to thesecond plunger rod position may require that a reconstitution time haselapsed since completion of movement of the plunger rod to the mixplunger rod position. The reconstitution time may be based on thetemperature. Receiving 6002 the temperature signal may be performedadditionally or alternatively after moving 6004 the plunger rod to themix plunger rod position, such as to determine the reconstitution time.

Receiving 6008 the trigger event may comprise receiving a user inputsignal from a user interface, e.g. receiving the trigger event from atrigger member, e.g. originating from a user pressing a button. Thetrigger event may originate from a user indicating a start of injection.The trigger event may originate from a user pressing a front part of theauto injector against an intended injection site. The trigger event maycomprise a contact member signal being indicative of a contact member ofthe auto injector being in a first contact member position.

Moving 6010 the plunger rod to the injection plunger rod position mayresult in ejection of the medicament through the cartridge outlet, suchas through a needle. Moving 6010 the plunger rod may follow reception ofthe trigger event 6008, e.g. after completion of movement 6006 of theplunger rod to the second plunger rod position

FIG. 11 shows a flow chart of an exemplary method 6000′. The method6000′ comprises the same steps of the method 6000 as explained inrelation to the previous figure. However the method 6000′ is an exampleof a method comprising an additional step of altering 6012 atemperature.

The method 6000′ comprises altering 6012 the temperature of the autoinjector and/or of the cartridge and/or of the medicament. Thetemperature may be altered following receiving 6002 the temperaturesignal indicative of the temperature of the medicament. The temperaturemay be altered while receiving 6002 the temperature signal. For example,the temperature signal may be received 6002 indicating that thetemperature is too low, the temperature may be raised by altering 6012the temperature, afterwards the temperature signal may again be received6002. This loop may continue until the temperature is within apredefined range. When the received 6002 temperature signal indicatesthat the temperature signal is within the predefined range, the method6000′ may continue to the next step of moving 6004 the plunger rod tothe mix plunger rod position. The method 6000′ may comprise altering6012 the temperature concurrently with other steps of the method, e.g.while moving 6004 the plunger rod to the mix plunger rod position, e.g.to optimize subsequent steps of the method 6000′.

FIG. 12 shows a flow chart of an exemplary method 6000″. The method6000″ comprises the same steps of the method 6000′ as explained inrelation to the previous figure. However the method 6000″ is an exampleof a method comprising additional steps of receiving 6014 a first inputsignal; detecting 6016 reception of the cartridge, e.g. in the cartridgereceiver of the auto injector; determining 6018 orientation of thecartridge; and reading 6020 a cartridge code feature; detecting 6022needle cover removal; moving 6024 the plunger rod to the first plungerrod position, such as a pre-mix plunger rod position; and detecting 6026resistance against movement of the plunger rod; and determining 6019reconstitution time.

Receiving 6014 the first input signal may comprise receiving a userinput signal from a user interface, e.g. originating from a userpressing a button. The first input signal may originate from a userturning on the auto injector.

Detecting 6016 reception of the cartridge may comprise detection of auser inserting the cartridge into the cartridge receiver through acartridge receiver opening. Detecting 6016 reception of the cartridgemay comprise detecting presence of a cartridge in the cartridgereceiver.

Receiving 6014 the first input signal and detecting 6016 reception ofthe cartridge may be interchanged.

Determining 6018 orientation of the cartridge may comprise determiningorientation by an orientation sensor, such as an accelerometer.Determining 6018 orientation of the cartridge may comprise determiningorientation of the auto injector. Determining 6018 orientation of thecartridge may comprise determining whether an outlet of the cartridge ispointing upwards.

The method 6000″ comprises reading 6020 a cartridge code feature. Thecartridge code feature may be indicative of one or more cartridgespecifications. The subsequent steps of the method 6000″ may compriseadaptations based on the cartridge specifications. For example,subsequent steps of the method 6000″ may be tailored to the specificcartridge received and identified.

Reading 6020 the cartridge code feature may be performed concurrentlywith receiving 6002 the temperature signal. However, alternatively, itmay be performed sequentially. For example, reading 6020 the cartridgecode feature may be performed prior to receiving 6002 the temperaturesignal, or reading 6020 the cartridge code feature may be performedafter receiving 6002 the temperature signal

Detecting 6022 needle cover removal may be a prerequisite of initiatingmovement of the plunger rod. For example, needle cover removal may beindicative of intended use of the cartridge received.

Moving 6024 the plunger rod to the first plunger rod position maycomprise initial movement of a first stopper of the cartridge, e.g.movement of the first stopper without commencing mixing of atwo-component medicament.

Moving 6024 the plunger rod to the first plunger rod position may followdetection 6016 of the cartridge being received in the cartridge receiverand reception 6014 of the first input signal. For example, moving 6024the plunger rod to the first plunger rod position may be performed onlyafter a cartridge is detected 6016 and the first input signal isreceived 6014.

Moving 6024 the plunger rod to the first plunger rod position may beperformed concurrently with the steps of receiving 6002 the temperaturesignal, optionally altering 6012 the temperature, and reading 6020 thecartridge code feature.

Detecting 6026 resistance against movement of the plunger rod may beperformed simultaneously with moving 6024 the plunger rod to the firstplunger rod position, as illustrated. Detecting 6026 resistance againstmovement of the plunger rod may be indicative of cartridge parameters ofthe cartridge received, such as whether the cartridge is new or used orflawed.

Moving 6004 the plunger rod to the mix plunger rod position may followreading 6020 the cartridge code feature, receiving 6002 the temperaturesignal, detecting 6022 needle cover removal, moving 6024 the plunger rodto the pre-mix plunger rod position, detecting 6026 resistance againstmovement of the plunger rod, and determining 6018 orientation of thecartridge.

Moving 6004 the plunger rod to the mix plunger rod position may be basedon one or more of the cartridge code feature, the temperature, needlecover removal, resistance against movement of the plunger rod and/ororientation of the cartridge.

Moving 6006 the plunger rod to the second plunger rod position mayrequire that a reconstitution time has elapsed since completion ofmovement of the plunger rod to the mix plunger rod position. The method6000″ comprises a step of determining 6019 the reconstitution time.Determining 6019 the reconstitution time may be based on one or more ofthe cartridge code feature, the temperature, needle cover removal,resistance against movement of the plunger rod and/or orientation of thecartridge. Determining 6019 the reconstitution time may comprisedetermining a first movement parameter, such as an amount of movement ofthe auto injector, such as shaking the auto injector and/or a number ofinversions of the auto injector. The first movement parameter may bedetermined based on an orientation signal, such as from an orientationsensor, such as an accelerometer. Determining 6019 the reconstitutiontime may comprise receiving an orientation signal.

Determining 6019 the reconstitution time may be determined based on acombination of the first movement parameter, the temperature and/or thecartridge code feature. Receiving 6002 the temperature signal may beperformed additionally or alternatively while determining 6019 thereconstitution time, such as to determine the reconstitution time.

Moving 6006 the plunger rod to the second plunger rod position may bebased on one or more of the cartridge code feature, the temperature,needle cover removal, resistance against movement of the plunger rodand/or orientation of the cartridge.

Moving 6010 the plunger rod to the injection plunger rod position may bebased on one or more of the cartridge code feature, the temperature,needle cover removal and/or resistance against movement of the plungerrod.

The method 6000 and/or the method 6000′ and/or the method 6000″ mayinclude a first step of receiving the cartridge.

FIGS. 13a-d schematically illustrates an exemplary user interface 1100of an exemplary auto injector 4, such as an auto injector 4 asillustrated in FIG. 1.

The user interface 1100 comprises a first output member 1110 asillustrated, e.g. a plurality of LEDs. The first output member 1110 mayprovide for a user output to a user. The first output member 1110 may beused to indicate a step in the procedure to the user and/or to indicatean error message. The first output member 1110 comprises a first LED1116, a second LED 1118, and a third LED 1120.

The user interface 1100 may comprise a second output member (not shown),e.g. a speaker.

The user interface 1100 comprises a contact member 1102, e.g. at aforward end of the auto injector 4. The contact member 1102 may beconfigured to be pressed against an injection site. The contact member1102 may serve as a third output member of the user interface 1100, e.g.the contact member 1102 may be configured to light up, such as flash.

The user interface 1100 comprises a first input member 1108, e.g. abutton. The first input member 1108 may provide for a user input from auser. For example, the first input member 1108 may be used for receivinga push from a user to proceed to a next step. The first input member1108 may serve as a fourth output member of the user interface 1100,e.g. the first input member 1108 may be configured to light up, such asflash.

FIG. 13a schematically illustrates a situation of the user interface1100 wherein none of the output members are active, e.g. the autoinjector 4 may be turned off.

FIG. 13b schematically illustrates a situation of the user interface1100 wherein the first input member 1108 and the contact member 1102light up, such as flashes. The first input member 1108 and the contactmember 1102 may flash synchronously and/or asynchronously. The situationshown may be a situation indicating that the user should press the firstinput member 1108 and/or insert a cartridge though the contact member1102. The situation shown may be a situation following that the autoinjector is turned on.

FIG. 13c schematically illustrates a situation of the user interface1100 wherein the first input member 1108 and the second LED 1118 lightup, such as flashes. The situation shown may be a situation indicatingthat the user should press the first input member 1108 to proceed to anext step. The situation shown may be a situation following mixing ofmedicament components and/or before performing an air-shot.

FIG. 13d schematically illustrates a situation of the user interface1100 wherein the first input member 1108 and the contact member 1102 andthe third LED 1120 light up, such as flashes. The first input member1108 and the contact member 1102 and the third LED 1120 may flashsynchronously and/or asynchronously. The situation shown may be asituation indicating that the user should press the contact member 1102against an intended injection site to inject the medicament. Thesituation shown may be a situation before injecting the medicament.

FIG. 14a-c schematically illustrate an exemplary movement of anexemplary auto injector 4, such as a movement of the first movementparameter.

FIG. 14a shows the auto injector 4 in a first position, wherein a firstend 4 a of the auto injector 4 points substantially upwards. A secondend 4 b of the auto injector 4 points substantially downwards.

FIG. 14b shows the auto injector 4 having been moved to a secondposition, wherein the first end 4 a of the auto injector 4 pointssubstantially downwards. The second end 4 b of the auto injector 4points substantially upwards.

FIG. 14c shows the auto injector 4 having been moved to a thirdposition, such as back to the first position, wherein the first end 4 aof the auto injector 4 points substantially upwards. The second end 4 bof the auto injector 4 points substantially downwards.

The first movement parameter may be indicative of number of inversionsof the auto injector 4, such as number of times the auto injector 4 hasbeen moved from the first position to the second position and optionallyto the third position, such as back to the first position. Theprocessing unit (not shown in FIG. 14) may be configured to detectand/or count number of inversions.

Although, in the example shown, the first end 4 a of the auto injector 4in the first and third positions points directly upwards, it may beenough that the first end 4 a of the auto injector 4 points within e.g.45 degrees of upwards.

Similarly, although in the example shown, the first end 4 a of the autoinjector 4 in the second position points directly downwards, it may beenough that the first end 4 a of the auto injector 4 points within e.g.45 degrees of downwards.

The reconstitution time may be dependent on inversions as described inrelation to FIG. 14. For example, reconstitution may require a certainnumber of inversions being performed, such as 5, with a frequency withina predefined range of frequencies, such as between 0.3 and 1.2 Hz. Forexample the reconstitution time may be the time used to perform thenumber of inversions. The number of inversions necessary and/or therange of frequencies may be determined based on the temperature, e.g.for higher temperatures less inversions may be needed, and for lowertemperatures more inversions may be needed. Alternatively oradditionally, the number of inversions necessary and/or the range offrequencies may be determined based on the cartridge code feature, e.g.the cartridge code feature may be indicative of the number of inversionsand/or frequency range for the inversions.

Although particular features have been shown and described, it will beunderstood that they are not intended to limit the claimed invention,and it will be made obvious to those skilled in the art that variouschanges and modifications may be made without departing from the spiritand scope of the claimed invention. The specification and drawings are,accordingly to be regarded in an illustrative rather than restrictivesense. The claimed invention is intended to cover all alternatives,modifications and equivalents.

The invention claimed is:
 1. An auto injector for administering amedicament, the auto injector comprising: a housing; a cartridgereceiver configured to receive a cartridge comprising a first stopperand a cartridge compartment containing the medicament, the cartridgecompartment having a first cartridge subcompartment containing a firstmedicament component of the medicament and a second cartridgesubcompartment containing a second medicament component of themedicament; a drive module coupled to move a plunger rod between aretracted plunger rod position and an extended plunger rod position, theplunger rod being configured to move the first stopper; a temperaturesensor configured to provide a temperature signal indicative of thetemperature of the medicament in the cartridge when received in thecartridge receiver; and a processing unit coupled to the temperaturesensor and the drive module; wherein the processing unit is configuredto: receive the temperature signal; control the drive module to move theplunger rod from a first plunger rod position to a mix plunger rodposition with a mix plunger rod speed, wherein the mix plunger rodposition is selected to position the first stopper in a position whereinthe first medicament component is mixed with the second medicamentcomponent, and wherein the movement from the first plunger rod positionto the mix plunger rod position is based on the temperature signal; andcontrol the drive module to move the plunger rod from the mix plungerrod position to a second plunger rod position after a reconstitutiontime has elapsed since completion of movement of the plunger rod to themix plunger rod position.
 2. The auto injector according to claim 1,wherein the reconstitution time is based on the temperature signal. 3.The auto injector according to claim 1, wherein the first plunger rodposition or the mix plunger rod position is based on the temperaturesignal.
 4. The auto injector according to claim 1, wherein the mixplunger rod speed is based on the temperature signal.
 5. The autoinjector according to claim 1, wherein the cartridge receiver isconfigured to receive a cartridge assembly comprising the cartridge anda cartridge code feature, and the auto injector comprising a code sensorconfigured to read the cartridge code feature, and wherein theprocessing unit is coupled to the code sensor and further configured toreceive from the code sensor a code signal indicative of the cartridgecode feature, and wherein the movement from the first plunger rodposition to the mix plunger rod position is based on the code signal. 6.The auto injector according to claim 5 wherein the reconstitution timeis based on the code signal.
 7. The auto injector according to claim 5,wherein the first plunger rod position or the mix plunger rod positionis based on the code signal.
 8. The auto injector according to claim 5,wherein the mix plunger rod speed is based on the code signal.
 9. Theauto injector according to claim 1 comprising an orientation sensorconfigured to provide an orientation signal indicative of theorientation of the cartridge when received in the cartridge receiver,and wherein the processing unit is coupled to the orientation sensor andfurther configured to receive the orientation signal, and wherein themovement from the first plunger rod position to the mix plunger rodposition is based on the orientation signal.
 10. The auto injectoraccording to claim 9, wherein the reconstitution time is based on theorientation signal.
 11. The auto injector according to claim 9, whereinthe mix plunger rod speed is based on the orientation signal.
 12. Theauto injector according to claim 1, wherein the processing unit isfurther configured to determine a first movement parameter based oncumulative movement of the auto injector.
 13. The auto injectoraccording to claim 12, wherein the reconstitution time is based on thefirst movement parameter.
 14. The auto injector according to claim 12,wherein the mix plunger rod speed is based on the first movementparameter.
 15. The auto injector according to claim 12, wherein thefirst movement parameter is indicative of number of inversions of theauto injector.
 16. The auto injector according to claim 12, wherein thefirst movement parameter is indicative of a frequency of movement of theauto injector.
 17. The auto injector according to claim 1, wherein thetemperature sensor comprises an infrared sensor.
 18. The auto injectoraccording to claim 1, further comprising a temperature control unitconfigured to alter the temperature of the cartridge when received inthe cartridge receiver.
 19. The auto injector according to claim 18,wherein the temperature control unit is configured to raise thetemperature of the cartridge.
 20. The auto injector according to claim19, wherein the temperature control unit comprises a resistive heatingelement.
 21. The auto injector according to claim 19, wherein thetemperature control unit comprises a dielectric heating element.
 22. Theauto injector according to claim 18, wherein the temperature controlunit is configured to lower the temperature of the cartridge.
 23. Theauto injector according to claim 18, wherein the temperature controlunit comprises a thermoelectric element.
 24. The auto injector accordingto claim 18, wherein the temperature control unit comprises a contactelement configured to be in contact with the cartridge when received inthe cartridge receiver.
 25. The auto injector according to claim 18,wherein the temperature control unit comprises a coil element configuredto surround an entire perimeter of the cartridge when received in thecartridge receiver.
 26. The auto injector according to claim 1, whereinthe first plunger rod position is a pre-mix plunger rod position, andthe pre-mix plunger rod position is selected to position the firststopper in a position wherein fluid communication between the firstcartridge subcompartment and the second cartridge subcompartment is notyet established.
 27. The auto injector according to claim 1, wherein thesecond plunger rod position is a prime plunger rod position, and theprime plunger rod position is selected to position the first stopper ina position wherein air in the cartridge compartment is reduced to anamount appropriate for injection.
 28. The auto injector according toclaim 1, wherein the processing unit is configured to control the drivemodule to move the plunger rod to an injection plunger rod position, andthe injection plunger rod position is selected to position the firststopper in a position wherein medicament in the cartridge compartment isminimized.
 29. The auto injector according to claim 28, wherein theprocessing unit is further configured to: receive a trigger event; andcontrol the drive module to move the plunger rod to the injectionplunger rod position following reception of the trigger event.
 30. Amethod for operating an auto injector comprising a cartridge receiverconfigured to receive a cartridge comprising a first stopper and acartridge compartment containing the medicament, the cartridgecompartment having a first cartridge subcompartment containing a firstmedicament component of the medicament and a second cartridgesubcompartment containing a second medicament component of themedicament, a plunger rod configured to move the first stopper, and atemperature sensor, the method comprising: receiving the temperaturesignal from the temperature sensor indicative of the temperature of themedicament when the cartridge is received in the cartridge receiver;moving the plunger rod from a first plunger rod position to a mixplunger rod position with a mix plunger rod speed, wherein the mixplunger rod position is selected to position the first stopper in aposition wherein the first medicament component is mixed with the secondmedicament component, and wherein the movement from the first plungerrod position to the mix plunger rod position is based on the temperaturesignal; and moving the plunger rod from the mix plunger rod position toa second plunger rod position after a reconstitution time has elapsedsince completion of movement of the plunger rod to the mix plunger rodposition.
 31. The method according to claim 30, wherein the secondplunger rod position is a prime plunger rod position, the prime plungerrod position being selected to position the first stopper in a position,wherein air in the cartridge compartment is reduced to an amountappropriate for injection.